When starting your FPV journey, most of the attention usually goes to the drone, video system, or controller, while the battery is often seen as nothing more than a simple power source. In reality, in the FPV hobby, it is one of the most important parts of the entire system. It determines not only how long you can fly, but also how the drone behaves in the air.
Oh, and its expensive. You’ll need more than one. So its good to know more about them 😉
Disclaimer
This article is for informational purposes only. By using batteries, you take full responsibility for your actions. Before doing anything with batteries, read the instructions provided with both the battery and the battery charger you are using.
Don’t stop there — be sure to also check the drone manufacturer’s instructions (if you purchased a pre-built drone), as well as the recommended voltage ratings specified in the documentation for your drone’s components.
Choosing the right battery allows you to get the most out of your drone. It has a direct impact on flight time, maximum motor power, drone weight, responsiveness to controls, and even flight safety. A battery that is too weak may not be able to deliver the required current, making the drone feel sluggish, causing the voltage to drop faster, and during more extreme maneuvers, the voltage may drop so low that the flight controller reboots (and the drone falls out of the sky).
On the other hand, a bigger battery isn’t always a better choice. A higher capacity might seem to mean longer flight time, but it also increases the weight of the drone. A heavier drone becomes less agile, requires more power to stay in the air, and in some cases may ultimately fly for even less time than with a smaller battery. That’s why you’re always looking for a balance between power, weight, and flight time.
You can compare it to a sports car. If you buy a Ferrari, you wouldn’t fill the tank with the lowest-quality fuel and still expect to get maximum performance. The same applies to FPV drone. Even the best frame, the most powerful motors, and the most advanced flight controller won’t reach their full potential if they’re powered by the wrong or a worn-out battery.
In this article, I’ll try to cover not only the different battery technologies, but also their markings, voltages, connectors, charging, maintenance, common mistakes, and plenty of other things I really wish I had known from day one in this hobby.
By understanding these basics, you’ll not only be able to keep your batteries in good condition for longer, but also get the maximum performance out of your drone.
Table of Contents
- Battery Markings
- Battery Capacity
- Cells — What Are They?
- Why Does a Battery Have Two Connectors?
- C rating
- Battery technologies
- Different Battery Voltages
- Battery Connectors
- Which Batteries for Which Drones?
- Battery Charging
- Battery Storage
- Voltage sag
- Internal Resistance — IR
- Battery Lifespan
- How Much Do Batteries Cost?
- When Is It Time to Say Goodbye to a Battery?
- Battery Disposal
- TL/DR – The Minimum You Should Remember
- The biggest and most common mistakes
- What do I use?
Battery Markings
The first time you pick up an FPV battery, it might seem like it’s covered in nothing but mysterious numbers and letters. 6S, 1300 mAh, 120C, XT60, LiHV — some kind of nonsense meant for someone with a PhD in physics…
In reality, these markings quickly tell you the most important characteristics of a battery — its voltage, capacity, how much current it can deliver, and even what kind of drone it is intended for.
Here are a couple of battery examples:
| What Do We See? Tattu R-Line Version 5.0 and Dogcom — the battery brand/manufacturer/model. 1400 mAh and 10000 mAh — battery capacity. It indicates how much energy the battery can store. Higher capacity usually means longer flight time, but it also increases the weight of the battery. We’ll talk more about choosing the right capacity later. 6 Cells and 6S2P — the number and arrangement of cells — this determines the battery voltage. 22.2 V — the battery’s nominal voltage. A single lithium cell has a nominal voltage of 3.7 V, so a 6S battery has a nominal voltage of 22.2 V (3.7 × 6 = 22.2 V). This marking is usually one of the first things that helps you determine which drone the battery is suitable for. | 150C and 10C — the maximum discharge rate. In theory, it indicates how much current the battery can deliver without damaging its cells. However, it’s worth knowing that C-ratings are not standardized across different manufacturers and are often optimistic, so you shouldn’t blindly rely on this number alone. 31.08 Wh and 222 Wh — the nominal amount of energy stored in the battery. This value isn’t always listed. It is calculated by multiplying the battery capacity by its nominal voltage. Li-ion battery — the battery technology. In the first example, it isn’t specified on the battery itself, but when purchasing the battery, its description would indicate that it is a LiPo battery. What else is important and usually specified when buying a battery? Battery connector — XT60 in both of these examples. We’ll talk more about connectors a little later. |
Battery Capacity
One of the first numbers you’ll see on a battery is its capacity, usually specified in mAh (milliamp-hours). It tells you how much energy the battery can store. Simply put, the higher the capacity, the longer the battery can power the drone. However, this doesn’t mean that a higher capacity is always the better choice.
Higher-capacity batteries are heavier. More weight means the motors have to lift a heavier drone, which increases energy consumption. Because of this, twice the capacity almost never means twice the flight time. In addition, higher-capacity batteries from the same manufacturer and product line usually cost more.
For example, if you use a 2200 mAh battery instead of a 1300 mAh battery on a 5-inch freestyle drone, the flight time will most likely increase, but the drone will become significantly heavier, less maneuverable, and slower to respond to your controls. A smaller battery, on the other hand, keeps the drone lighter and provides a more dynamic flight. It’s also worth mentioning that you shouldn’t use batteries with drastically different weights on the same drone, because the change in weight may require you to constantly adjust the drone’s settings (perhaps even the camera angle) to make it fly the way you’re used to.
That’s why, when choosing battery capacity, it’s worth already knowing what the drone will be used for and what style you plan to fly. It’s always a compromise between flight time and drone weight. Freestyle pilots usually choose lighter batteries, while Long Range drones often use higher-capacity Li-ion batteries because the main priority there is achieving the longest possible flight time, while maneuverability is less important.
Cells — What Are They?
It’s worth understanding what a cell actually is 🙂 The simplest way to think of it is as a single individual battery element. For example, a single AA or AAA battery is essentially one cell. Of course, they use completely different chemistry and their voltage differs from lithium batteries, but it’s still a pretty good analogy for understanding the concept.
In the FPV world, lithium batteries are most commonly used, so a single cell has a nominal voltage of around 3.7 V. By connecting several of these cells together into a pack, we get the battery that we connect to the drone. In lithium-ion (Li-ion) batteries, the cells are usually cylindrical and come in standardized sizes, such as 18650, 20700, or 21700. These numbers aren’t random — they indicate the dimensions of the cell in millimeters. For example, an 18650 cell is approximately 18 mm in diameter and 65 mm long, while a 21700 cell is 21 mm in diameter and 70 mm long.
FPV LiPo batteries, on the other hand, use flat pouch cells rather than cylindrical ones. We usually can’t even see the individual cells from the outside because the entire cell pack is wrapped in protective heat-shrink film.
Regardless of whether a battery consists of cylindrical Li-ion cells or flat LiPo cells, the way those cells are connected determines markings such as 4S, 6S, or 6S2P.
Cell Count and Markings
One of the most important markings on an FPV battery is a number followed by the letter S. It indicates how many lithium cells are connected in series. Each lithium cell has a nominal voltage of around 3.7 V, so as the number of cells increases, the total battery voltage increases as well.
For example, a 4S battery consists of four cells connected in series — 14.8 V, while a 6S battery has six cells — 22.2 V. This is why a 6S battery shouldn’t be thought of as simply “bigger” than a 4S battery. It simply operates at a higher voltage and is therefore usually used in drones whose electronics and motors are designed for it.
The most common configurations are:
| S marking | Celių count | Nominal voltage |
|---|---|---|
| 1S | 1 | 3.7 V |
| 2S | 2 | 7.4 V |
| 3S | 3 | 11.1 V |
| 4S | 4 | 14.8 V |
| 6S | 6 | 22.2 V |
| 8S | 8 | 29.6 V |
What Does the Letter P Mean?
Sometimes you’ll see an additional marking on batteries, such as 6S2P or 4S2P. The letter P means that the cells are connected in parallel. Connecting cells in parallel does not increase the battery voltage, but it does increase its capacity and allows it to deliver more current. For example:
- 6S1P — six cells connected in series. This is a typical 6S LiPo battery with 6 cells.
- 6S2P — six groups connected in series, but each group contains two cells connected in parallel. This battery has a total of 12 cells.
For example, if 3000 mAh cells are used:
- 6S1P battery will have a capacity of 3000 mAh.
- 6S2P battery will have a capacity of 6000 mAh.
- 6S3P battery will have a capacity of 9000 mAh.
Of course, the battery’s weight and physical size increase as well.
Why Don’t LiPo Batteries Usually Have a P Marking?
On many typical LiPo batteries, you’ll only see 4S, 6S, or 8S, without any 1P marking. This is because almost all such batteries are made with a single cell in each series group, meaning they are essentially 4S1P, 6S1P, and so on. The 1P is simply omitted because it is considered implied.
With Li-ion batteries, on the other hand, connecting cells in parallel is very common, so the P marking is seen much more often
Why Does a Battery Have Two Connectors?
If you’ve only used regular household batteries or rechargeable batteries until now, you might be surprised to see that most FPV batteries have two connectors. Why are both needed?
Almost all 2S and larger batteries (with rare exceptions) have two separate connectors. The first is the main power connector, which has two wires: positive (+) and negative (−). This is how the battery supplies power to the drone during flight, and during charging, the main charging current flows through this connector.
The second is the balance connector. Its wires are much thinner because only a small amount of current flows through them. The purpose of this connector is to allow the charger to monitor the voltage of each cell individually. Balancing is the process in which the charger equalizes the voltage of all the cells in the battery (if it notices that one cell is charging faster than the others, it slows down the charging of that cell slightly).
Why is this important? Even though all the cells in a battery are the same, over time their voltages begin to differ slightly. One cell may charge faster, while another may charge more slowly. If the battery were charged only through the main connector, the charger would see only the total battery voltage and wouldn’t be able to determine whether all the cells were charged equally.
That’s why both connectors are used when charging multi-cell batteries — the main connector carries most of the power, while the balance connector allows the charger to monitor each cell individually. During flight, only the main power connector is used because the drone only needs the battery’s total voltage.
C rating
One of the most commonly advertised battery parameter is the discharge C rating. Manufacturers often proudly display numbers such as 100C, 120C, or even 150C, creating the impression that the higher the number, the better the battery. But what does this C actually mean, and is it really worth paying attention to?
It indicates the maximum discharge current that the battery can theoretically deliver.
The higher the C rating, the more current the battery can supply to the motors. In practice, this means that the drone will be better able to maintain its voltage when you suddenly increase the throttle, there will be less voltage sag (a drop in voltage under load), and the flight will feel more dynamic.
What is 1C? It is the discharge current that would theoretically fully discharge the battery in one hour. For example, if the battery capacity is 1300 mAh (1.3 Ah), then:
| C rating | Current; A |
|---|---|
| 1C | 1.3A |
| 10C | 13A |
| 50C | 65A |
| 100C | 130A |
| 120C | 156A |
There is one catch, though. Unlike cell count or capacity, the C rating is not strictly standardized. Manufacturers determine it using their own testing methods, so two batteries from different manufacturers that both have 120C printed on them may have significantly different real-world maximum discharge capabilities. That’s why measurements from independent testers are often more useful than relying solely on the C rating declared by the manufacturer. Of course, if you’re comparing batteries from the same manufacturer, things are a little simpler.
For this reason, experienced FPV pilots usually treat the C rating only as a rough guideline. Independent testing, the experience of other pilots, or the battery’s internal resistance increasing over time can tell you much more about its actual quality.
So, when choosing a battery, you shouldn’t blindly chase the highest possible C rating. It is much more important to choose batteries from a reputable manufacturer that can maintain stable voltage under real-world conditions and continue performing reliably over many flights.
Of course, this naturally raises another question — where do you actually use that C rating? If a battery can deliver 156 A, how do you know whether that’s enough for your drone?
The battery is connected to the ESC. An ESC always has its own current rating. For example, a SpeedyBee 45A 4-in-1 ESC means that each individual ESC on the board (there are actually four ESCs on a 4-in-1 board) can handle up to 45 A of current flowing to a motor. Four motors connected to four separate ESCs means 45 × 4 = 180 A.
However, it’s important to understand that these are the maximum current limits the ESCs are designed to handle. The actual current drawn from the battery depends on the motors connected to them. If you’re buying a pre-built drone from a manufacturer, you generally don’t need to worry about this. If you’re building the drone yourself, it’s worth checking the motor specifications.
For example, let’s look at a test table provided by one FPV motor manufacturer:
We can see that with the specified propeller and a 6S battery, the motor draws around 35.5 A at maximum power. So, with four motors, that would be: 35.5 A × 4 = 142 A
But that’s only if you’re at 100% throttle, which doesn’t happen very often or for very long during a real flight. And even when it does, it usually lasts only a few seconds.
By the way, the C rating does not give the drone more power. If two batteries of the same quality differ only in that one is rated at 100C and the other at 150C, the drone will not necessarily be faster with the 150C battery. A higher C rating simply means that the battery can theoretically handle higher loads better and experience less voltage sag. If the 100C battery already meets the drone’s requirements, the 150C battery won’t provide any additional benefit.
One more “by the way” — the C rating applies not only to a battery’s discharge current, but also to its charging current.
Battery Technologies
In the FPV world, four lithium battery technologies are most commonly used (or, more precisely, two technologies, each with two variations). Although they all work on the same basic principle, each has its own advantages and disadvantages.
One technology allows you to squeeze out maximum power for acrobatic flying, another lets you fly several times farther, while a third is simply an improved version of the classic LiPo. That’s why, when choosing a battery, it’s important to understand not only its capacity or cell count, but also the battery technology itself.
Lithium Polymer — LiPo
LiPo, or lithium polymer, batteries are almost certainly the most popular choice in the FPV world. You’ll find them in nearly all freestyle, racing, and cinewhoop drones. Their biggest advantage is their ability to deliver very high current. That’s why, when you suddenly increase the throttle, the motors instantly get the power they need, while the drone remains fast and highly maneuverable.
On the other hand, this comes at a cost. Compared with lithium-ion (Li-ion) batteries, LiPo batteries store less energy for the same weight, so flight times are usually shorter. More importantly, they are more sensitive to improper storage and require more care.
If your goal is acrobatic flying or racing, LiPo is still the best choice.
Advantages
- very high current output;
- excellent for aggressive flying;
- wide range of options available on the market.
Disadvantages
- shorter flight time;
- require more maintenance.
High-Voltage Lithium Polymer — LiHV
At first glance, LiHV batteries look almost identical to LiPo batteries. And in fact, the two technologies are very closely related. The main difference is that a single LiHV cell can be charged up to 4.35 V, while a standard LiPo cell is charged up to 4.20 V. Because of this, the battery can store slightly more energy and provide slightly more power at the beginning of a flight.
However, the difference isn’t huge. In most cases, we’re talking about only a few extra percent of capacity or slightly higher voltage during the first few minutes of flight.
The most important thing to remember is that LiHV batteries need to be charged using a dedicated LiHV charging mode. If you charge them like regular LiPo batteries to 4.20 V, they simply won’t be fully charged. I’ve made this mistake more than once myself when I was in a hurry.
Advantages
- slightly higher capacity than LiPo;
- higher initial voltage than LiPo
Disadvantages
- require a dedicated LiHV charging mode;
- the advantage over LiPo isn’t very significant;
- batteries degrade faster than LiPo.
Lithium-Ion — Li-ion
If LiPo batteries are designed for maximum power and speed, lithium-ion batteries are focused on achieving the highest possible efficiency and flight time.
These batteries can store significantly more energy for the same weight, making them an excellent choice for long-range flights. This is exactly why many 7–10-inch FPV drones use Li-ion batteries.
However, higher energy density comes at a cost. Li-ion cells cannot deliver as much current as LiPo cells, so they are generally not suitable for aggressive freestyle or racing flights.
Li-ion batteries are most commonly built using cylindrical cells, such as 18650 and 21700 cells.
Advantages
- long flight time;
- high energy density;
- longer lifespan.
Disadvantages
- lower maximum discharge current;
- not suitable for highly dynamic flying.
Tabless Lithium-Ion
In recent years, the term tabless has been coming up more and more often. This isn’t a new battery chemistry — it’s an improved Li-ion cell design. In conventional Li-ion cells, current flows to the external terminals through narrow metal strips called tabs. In tabless cells, these strips are practically eliminated — current is distributed across a much larger area of the electrode. This reduces internal resistance, allows cells to generate less heat, and enables them to deliver more current. In other words, tabless technology brings Li-ion performance closer to LiPo while retaining the main advantage of Li-ion — high energy density.
However, it’s worth keeping in mind that even the most advanced tabless Li-ion cells still cannot match high-quality LiPo batteries in many cases when very high instantaneous current is required.
Advantages
- lower internal resistance;
- higher possible discharge current as a result;
- less heat generation;
- excellent choice for long range drones.
Disadvantages
- higher price;
- still falls behind LiPo in maximum power output.
Different Battery Voltages
Up to this point, I’ve mainly used one term when talking about battery voltage — nominal voltage. But when discussing battery voltages, several other voltage values are commonly mentioned as well. Why do we need them, and what do they mean?
Each of these voltage values means something different and is used in different situations. For example:
- Nominal voltage — this is the average voltage of a battery cell, its design voltage, or simply its voltage “on paper” (OK, I agree — this is probably the one you’ll use the least).
- Fully charged voltage — a very important number. This is the maximum voltage to which you can charge the battery. Charge it less — OK, no problem. You’ll simply fly for less time. Charge it higher — a big no, no, no. At the very least, you’ll accelerate cell degradation; in the worst case, you’ll create a bonfire (fire) on your table.
- Storage voltage — keeping lithium batteries fully charged for long periods of time isn’t good for them. Doing so also accelerates degradation. However, there is something called storage voltage, at which a battery can be stored for a very long time with practically no degradation (according to manufacturers, only a few percentage points of capacity are lost).
- Recommended landing voltage — this is a recommended voltage. And it’s recommended for a reason — if you allow the voltage to drop below this level during flight, you risk reaching the point where the drone’s electronics simply no longer have enough voltage and the drone “shuts down.” You’re flying along and suddenly you see the drone simply start coming down on its own (unfortunately, I don’t have the link, but just a few days ago I saw a video on Instagram where a guy got so caught up in filming with his drone that he completely forgot to keep an eye on the voltage. And, of course, while flying over water — bam, there’s not enough voltage. Well, at least his goggles captured a nice video of an expensive lesson).
- Fully discharged voltage (practically empty) — you definitely won’t be able to use a battery at this voltage to fly a drone anymore. You might still manage to power your FPV goggles with it, but you risk discharging the battery to a dangerously low level.
- Dangerously discharged (cut-off voltage) — if you discharge a battery below this voltage, irreversible processes begin that damage the battery. Although the battery most likely won’t catch fire simply because you discharged it this far, but!!! It may catch fire later when you try to charge it.
Typical Voltage per Cell:
| Battery state of charge | LiPo | LiHV | Li-Ion & Li-Ion Tabless |
|---|---|---|---|
| Nominal voltage | 3.7 V | 3.8 V | 3.6-3.7 V |
| Fully charged voltage | 4.20 V | 4.35 V | 4.20 V |
| Storage voltage | 3.8–3,85 V | 3.8–3.85 V | 3.60–3.80 V |
| Recommended landing voltage | ~3.5 V | ~3.5-3.6 V | ~3.2–3.3 V |
| Practically empty. Do not arm the drone at this voltage, and during flight, avoid letting the battery reach this level. | ~3.3 V | ~3.4 V | ~3.0 V |
| Cut-off voltage. It’s better not to use the battery at all. | <3.0 V | <3.0 V | <2.5–2.8 V |
The voltage you see during flight depends on the load. When you suddenly increase the throttle, it can temporarily drop by several tenths of a volt due to an effect known as voltage sag. Once you reduce the throttle, the voltage rises again, so when estimating how much battery capacity you have left, you should consider not only the instantaneous voltage but also the voltage after it has stabilized.
Battery Connectors
When choosing a FPV battery, it’s important to pay attention not only to its capacity or cell count, but also to its power connector. This is what transfers electrical power from the battery to the drone. If the connectors on the battery and the drone don’t match, you simply won’t be able to connect them without an adapter or replacing the connector. OK, maybe buying a drone and a battery with different connectors is a somewhat less common situation, but when it comes time to charge the battery and your battery charger doesn’t have the right connector — you’ll have to spend some time buying an adapter or soldering one yourself.
Different sizes of drones use different connectors. For small tinywhoops, keeping the weight as low as possible is one of the most important considerations, so very compact connectors are used. Larger 5- or 7-inch drones, on the other hand, can draw more than 100 A of current, so they require much more robust connectors.
Below are the battery connectors you’ll most commonly encounter in FPV hobby.
PH2.0
PH2.0 was the standard connector for 1S tinywhoop batteries for a long time. It is small, inexpensive, and widely available, but it has one significant drawback — due to its higher contact resistance, it causes greater voltage drop (voltage sag) under heavier loads. For this reason, it has increasingly been replaced by more modern connectors in recent years.
Most commonly used for: older 1S tinywhoop drones.
BT2.0
BT2.0 — one of the most popular modern 1S connectors, developed by BetaFPV back in 2019. It has lower contact resistance than PH2.0, allowing it to carry more current while reducing voltage drop.
If you’re choosing a new 1S tinywhoop, BT2.0 will usually be a better choice than PH2.0.
Most commonly used for: 1S tinywhoop drones.
GNB27
GNB27 — another newer 1S connector, developed by GNB (Gaoneng) around 2020 (most likely as a response to BT2.0, because of licensing fees, or simply as part of the search for the best connector for tinywhoops). It was designed to minimize power losses and provide greater durability. It is slightly larger than BT2.0, but in return offers lower resistance and less voltage drop. As far as I understand, this connector never really caught on, and GNB later released another connector — the A30.
Most commonly used for: 1S tinywhoop drones.
A30
A30 appeared around 2023 as an alternative to BT2.0. Its contacts also have low resistance, allowing it to efficiently carry the high currents required by small 1S drones.
Although its technical characteristics are very similar to BT2.0, the two connectors are not fully compatible with each other. From what I found online, drones with a BT2.0 plug can be used with batteries that have an A30, but not the other way around. Just like BT2.0, this connector has become widely adopted for tinywhoops in the FPV world. BT2.0 battery chargers can also be used to charge A30 batteries.
Most commonly used for: 1S tinywhoop drones.
EM2.0
Another connector for small drones, this time from EMAX, a manufacturer of drones and drone parts. It doesn’t seem to have gained much popularity in the FPV world. Personally, I would avoid batteries with this connector because of their likely limited use (unless you have an EMAX drone with this connector and don’t plan to expand your drone fleet).
Most commonly used for: 1S tinywhoop, 2S toothpick drones.
NX69
The newest member of the 1S tinywhoop battery connector family comes from NewBeeDrone. It appeared very recently — in the second half of 2025. As with A30, GNB27, and EM2.0, it most likely emerged as an attempt to avoid BT2.0 licensing costs.
It’s still too early to tell whether this newest connector will catch on. Although its technical specifications don’t seem to make it significantly more advanced than the alternatives, it does have one major advantage over all the others. This connector is an improved version of PH2.0, and NX69 batteries can be used with drones that have PH2.0 connectors (unfortunately, drones with NX69 connectors cannot use PH2.0 batteries).
Most commonly used for: 1S tinywhoop drones.
BT3.0
BT3.0 is a connector developed by BetaFPV for 2S micro drones that require higher current. It can carry significantly more power than BT2.0 while remaining lightweight.
Most commonly used for: 2S tinywhoops and lightweight micro drones.
XT-30
XT30 — one of the most popular connectors for smaller FPV drones. It is lightweight, reliable, and can easily handle currents of tens of amps.
Most commonly used for: 2S–4S drones, although it can sometimes be found on 1S batteries and even 6S batteries.
XT-60
XT60 has been the standard connector for medium- and large-sized drones in the FPV world for many years. It can reliably handle very high currents, which is why it is used on almost all 5-inch freestyle and cinewhoop drones, as well as many long range drones.
Most commonly used for: If you buy a 5 or 7-inch FPV drone, there’s a very good chance it will have an XT60 connector. 3S-6S batteries.
XT-90
XT90 is a larger version of the XT60 connector, designed to handle even higher currents. Its larger contacts generate less heat under heavy loads, making it better suited for high-power systems.
Most commonly used for: In the FPV world, XT90 is most commonly used on large 10-inch and larger long range drones. It is rarely found on typical 5-inch freestyle drones, as it would only add extra weight without providing any real benefit.
| Connector | Nominal current | Max current | Commonly used with: |
|---|---|---|---|
| PH2.0 | 2A | 2A | 1S |
| BT2.0 | 9A | 15A | 1S |
| A30 | 15A | 30A | 1S |
| GNB27 | 9A | 15A | 1S |
| EM2.0 | 10A | 20A | 1S-2S |
| NX69 | ? | 26A | 1S |
| BT30 | 12A | 20A | 2S |
| XT30 | 15A | 30A | 2S-4S |
| XT60 | 30A | 60A | 4S-6S |
| XT90 | 45A | 90A | 6S+ |
Looking at this table, a more attentive reader might ask: “Wait a minute — the connector specifications list currents this low, but the C ratings of the batteries suggest they can deliver several times more current.” The same applies to the SpeedyBee ESC discussed earlier — 45 A for each of the four motors.
The table is intended more as a general comparison between the different connectors. Connector manufacturers are very conservative when specifying current ratings. It’s worth keeping in mind that FPV drone flights rarely last longer than 5–10 minutes, while the current ratings in connector specifications refer to continuous long-term use (not for a few days, but for weeks or months).
BetaFPV itself, for example, specifies a 9 A rated current for the BT2.0 connector, yet on the LAVA 2 1S battery page, the discharge curve for the 680 mAh battery is shown at 39 A. In addition, a 680 mAh battery with a 95C rating theoretically has a maximum discharge current of almost 65 A.
Which Batteries for Which Drones?
The table below shows the most commonly used configurations. Depending on the specific drone model or its intended purpose, the manufacturer may use a different cell count, battery technology, or connector.
| Drone | Cell count | Technology | Most common connector |
|---|---|---|---|
| 65, 75 mm Tinywhoops | 1S | LiHV | BT2.0, A30 |
| Toothpick | 1S-2S | LiHv/LiPo | BT2.0, BT3.0, A30, XT30 |
| 3” Freestyle | 4S, sometimes 6S | LiPo | XT30 |
| 5” Freestyle | 4S-6S | LiPo | XT60 |
| 7” Long Range | 6S | Li-Ion, LiPo (less common) | XT60 |
| 10” Long Range | 6S-8S | Li-ion | XT60/XT90 |
Battery Charging
Charging Phases
Modern FPV battery chargers charge batteries using the CC/CV (Constant Current / Constant Voltage) algorithm. Simply put, charging takes place in two stages.
Constant Current (CC)
During the first charging phase, the charger maintains a constant current. The battery is charged at the selected charging current (e.g., 1 A, 2 A, or 5 A), while its voltage gradually increases. This phase makes up most of the charging process and usually continues until one of the cells reaches its maximum allowed voltage — 4.20 V for LiPo and Li-ion or 4.35 V for LiHV.
Constant Voltage (CV)
Once at least one cell reaches its maximum voltage, the charger switches to the second phase — Constant Voltage (CV) mode. At this stage, the charger no longer allows the voltage to rise above the set limit. Instead, it gradually reduces the charging current until the battery is fully charged. This is why the last few percent of the charging process usually take longer.
Main Battery Charging Modes
Balance Charge
The charger not only charges the battery to the specified maximum voltage, but also continuously monitors the voltage of each individual cell through the balance connector. If one cell charges faster than the others, the charger slows it down slightly and allows the remaining cells to catch up. This way, all cells finish charging at the same voltage. If you’re not sure which mode to choose when charging a battery, always choose Balance Charge. You can’t really go wrong.
Some chargers also don’t have separate Charge and Balance Charge modes and instead provide a single Charge mode. In that case, if the balance connector is connected, the charger will balance the cells automatically. When I bought my HOTA F6 charger, I was initially very surprised when I couldn’t find a Balance Charge mode. Only after going through the user manual did I find a note explaining that everything was fine — you simply need to connect the balance connector, and the charger detects it and automatically performs balancing
(Other possible mode names: Charge, Balance CHG)
Storage
This is one of the most important modes, although beginners sometimes tend to forget about it. In this mode, the charger automatically charges or discharges the battery to its storage voltage. If you don’t plan to fly for the next few days, it is recommended to leave your batteries at this voltage.
(Other possible mode names: StoCHG, Storage Charging)
Other Battery Charging Modes
I’ll be honest — I’m not sure whether I’ve ever actually used any of these modes to this day.
Charge
This is the simplest battery charging mode. The charger charges the battery to its maximum voltage, but does not always actively balance all the cells (or may not balance them at all). On some chargers, balancing still takes place if the balance connector is connected, but not as precisely as when using Balance Charge mode.
Fast Charge
This mode is designed to charge the battery as quickly as possible. Any charging at a rate higher than 1C is considered fast charging. The charger focuses most of the charging process on the main charging current and spends less time on balancing. As a result, charging is completed faster.
Fast charging can be useful during races or at the flying field when you need to get back in the air as quickly as possible. However, for everyday use, Balance Charge is recommended because it provides more precise cell balancing.
Discharge
In this mode, the charger discharges the battery to a selected voltage. It is most commonly used in two situations: before disposing of a heavily damaged or no-longer-usable battery, or to prepare a battery for long-term storage (if the charger does not have a Storage mode). Not all chargers allow you to discharge a battery all the way down to 0 V
Destroy / Disposal
Some chargers have a function that allows you to completely discharge a battery. Not down to “practically empty” at around 3 V, but all the way down to 0 V. I think this is a really useful feature for safely disposing of lithium batteries.
Battery Chargers
There’s an especially wide range of options here, both for charging 1S batteries and for 2S and larger batteries. Below, I’ve put together a fairly long list, but it still includes only some of the more popular models. It is definitely not a complete list of battery chargers.
1S battery chargers
| Model | Comment | URL |
|---|---|---|
| GEPRC WooPower W63 | Charges up to 6 batteries with BT2.0, A30, and PH2.0 connectors. | URL |
| Vifly WhoopStor V3 | Charges up to 6 batteries with BT2.0, A30, and PH2.0 connectors. | URL |
| BetaFPV HexaCharger / PRO | Charges up to 6 batteries with BT2.0, A30, and PH2.0 connectors. | URL |
| BetaFPV 6 Ports 1S battery charger | Charges up to 6 batteries with BT2.0, A30, and PH2.0 connectors. It’s a slightly older model than the HexaCharger and doesn’t have a screen for monitoring the charging process — but it’s significantly cheaper. | URL |
| BetaFPV BT2.0 Battery Charger | Charges up to 2 batteries with BT2.0 connectors. It can also be used to quickly check the battery voltage. Very convenient when you’re out flying. | URL |
2S battery chargers
Chargers for Higher Cell Counts
All of these models have XT60 and balance connectors. If you want to charge a battery with a different connector, you’ll need an adapter (for example, XT30 ↔ XT60).
In addition, most chargers use DC input for power, so you may also need to get a power supply (who doesn’t have an old laptop power adapter lying around somewhere? Of course, you might need to do a little soldering to replace its connector with an XT60 or XT90).
Most of these chargers can also measure the internal resistance of batteries.
| Model | Comment | URL |
|---|---|---|
| 1 channel – charge 1 battery at a time | ||
| SkyRC B6neo series | Designed for charging 1S–6S batteries. It can only be powered from a DC source (XT60 or USB-C). Thanks to its small size, it’s very convenient to use out in the field when you need to quickly check the condition of a battery. B6neo line includes several models. There is also a model that can be powered directly from an AC outlet (B6ACneo: https://www.skyrc.com/b6acneo ) | URL |
| ISDT Q6 Nano | Designed for charging 1S–6S batteries. The Q8 and Q8 Max chargers from the same Q series are designed for 1S–8S batteries (also single-channel). Like the SkyRC B6neo, it is convenient to use out in the field. It also has a function that allows you to completely discharge a battery down to 0 V (“destroy” the battery). | URL |
| HOTA T8 | Designed for charging 1S–8S batteries. It can only be powered from a DC source (XT60). It is one of the more affordable models capable of charging 8S batteries. Like the SkyRC B6neo, it is convenient to use out in the field. The T8 Ultra model can also be powered from an AC outlet. | URL |
| iSDT 608AC | Designed for charging 1S–6S batteries. Similar to the ISDT 608PD, but with the addition of AC input. It also has a function that allows you to completely discharge a battery down to 0V (“destroy” the battery). | URL |
| ISDT P20 | Designed for charging 1S–8S batteries. It also has a function that allows you to completely discharge a battery down to 0 V (“destroy” the battery). | URL |
| 2 and more channel chargers | ||
| HOTA D6 Pro | A dual-channel charger designed for charging 1S–6S batteries. It can be powered from either AC or DC (XT60 connector). It also has a wireless charging function, which is convenient for charging your phone. | URL |
| HOTA F6 | A four-channel charger designed for charging 1S–6S batteries. It can only be powered from a DC source (XT60). The F6 Ultra model can be powered from either AC or DC (XT90 connector). | URL |
| SkyRC D200Neo | A dual-channel charger designed for charging 1S–6S batteries. It can be powered from either AC or DC (XT60 connector). It also has a USB-C PD output, which can be used to charge your phone. | URL |
| ToolkitRC Q6AC | A four-channel charger designed for charging 1S–6S batteries. It can be powered from either AC or DC (XT90 connector). It also has a wireless charging function, which is convenient for charging your phone. | URL |
Parallel Charging — Dangerous but Useful
Originally considered to skip this topic at all, but I would be doing readers a disservice if I left it out. This is definitely not a beginner topic for one fairly simple reason — the risks involved. A single careless mistake can very quickly cause a serious fire.
To use parallel charging, you need to prepare properly. The batteries must use the same battery technology and have the same cell count. Their state of charge (current voltage) must also be very similar. In some sources, I found a recommendation that the difference between corresponding cells should not exceed 0.1 V. It is also recommended to charge in a fire-resistant environment.
And one more thing — if one of the connected batteries is damaged or has severely unbalanced cells, very high equalization currents can flow between the batteries as soon as they are connected. In extreme cases, this can damage the batteries or even cause a fire.
It is precisely because of all these requirements — for the batteries themselves, their state of charge, and the charging environment — that parallel charging is not really a beginner topic.
Despite all the risks, it is a very efficient way to charge, for example, six batteries at the same time using just one charger channel. Parallel charging boards are significantly cheaper than chargers with the same number of independent channels. In addition, all the batteries charge at the same time, so you don’t have to keep swapping them around.
So what exactly makes it so dangerous? When batteries are connected in parallel, they immediately begin equalizing their voltages. If one 6S battery is at 25.2 V and another is at 22.5 V, the batteries themselves will try to equalize those voltages. And that means the instantaneous current can be enormous. While the battery with the higher voltage may have a high discharge C rating, the battery with the lower voltage certainly won’t be expecting that kind of charging current. As I mentioned earlier, batteries are generally recommended to be charged at around 1C.
Personally, I use a HOTA F6 four-channel charger, which is more than enough for my needs. Is it the most economical solution? Probably not. But simplicity and safety are more important to me. Four independent channels allow me to charge different batteries at the same time without having to worry about whether they are compatible with each other, so for me, that convenience is worth the higher price.
And now, again, I’m going to contradict myself straight away — if I were racing and needed to charge as many batteries as possible as quickly as possible, parallel charging would be my choice. Of course, first I’d actually have to buy a parallel charging board, which I don’t currently own.
Battery Storage
If you asked FPV pilots who have been in this hobby for at least a few years – what shortens battery lifespan the most, many of them wouldn’t say “flying too aggressively,” but rather improper battery storage.
Lithium batteries don’t like extremes. They don’t like being either fully charged or fully discharged. If you know you won’t be flying for the next few days, it’s best to leave your batteries at storage voltage — around 3.8–3.85 V per cell.
Why Shouldn’t You Store Fully Charged Batteries for Long Periods?
More intensive chemical reactions take place inside a fully charged battery. Because of the high voltage, the cells age faster, their internal resistance increases, their capacity decreases, and the battery gradually loses its ability to deliver high current.
If you fully charge a battery in the evening and go flying the next day, nothing bad will happen. The problem arises when batteries sit at 100% charge for weeks or months.
Fun fact: DJI camera drones often have smart charging hubs that hold several batteries, with built-in BMS (Battery Management System) functionality that ensures that if the batteries are left fully charged, they are automatically discharged to storage voltage.
Why Shouldn’t You Store Fully Discharged Batteries?
The other extreme is a fully discharged battery. Even when it isn’t being used, a battery gradually loses voltage due to self-discharge. If it is already close to its minimum safe voltage, after a few weeks or months its cells may drop below the safe voltage level.
When this happens, irreversible chemical processes begin — the battery loses capacity, its internal resistance increases, and in some cases it may become completely unusable.
Storage Mode — The Best Compromise
Around 3.8 V per cell is considered the optimal voltage for long-term storage. At this voltage, chemical processes inside the battery occur slowest, so it ages significantly slower than when stored fully charged or fully discharged.
That’s exactly why most modern FPV battery chargers have a Storage charge/discharge mode. If you don’t plan to fly for the next few days, it’s worth using it — it’s one of the simplest ways to noticeably extend the lifespan of your batteries.
By the way, if you’ve finished flying and, after a few minutes, once the battery voltage has stabilized, you see that it is around 3.8–3.85 V per cell, then the battery is already practically at storage voltage and there’s no need to do anything else.
P.S. In the list of recommended battery chargers, I tried to check each model to make sure it has a Storage mode. Some models didn’t make the list for this particular reason (such as the iSDT 608PD or iSDT P10).
Heat — the Biggest Enemy of Batteries
If high voltage accelerates battery aging, high temperatures speed up this process even more. Especially dangerous situation is leaving fully charged batteries in a car during the summer. The temperature inside a car parked in the sun can rise to 120-160ºF/50–70°C, and under these conditions, batteries age even faster than when stored at room temperature.
That’s why it’s good practice not to leave batteries in the car any longer than necessary and to move them to a cooler place after flying.
How to Store Batteries Safely?
Although modern LiPo and Li-ion batteries are generally quite safe, they can catch fire if they are used improperly or damaged. Such incidents are not common, but the consequences can be very serious (extinguishing the resulting fire is almost impossible — you basically have to “wait for the lithium to burn out”). For this reason, it’s worth following a few simple rules.
- As I’ve already mentioned several times, I’ll repeat it once again — first of all, store your batteries at storage voltage (3.8–3.85 V). This will not only extend their lifespan but also reduce the risk if a battery is damaged or starts to overheat;
- The storage location should be dry, cool, and protected from direct sunlight. Avoid leaving batteries in a car, on a windowsill, or in other places where the temperature can rise significantly;
- If you have several or a dozen batteries, it’s worth storing them in a fire-resistant container. The most popular option is a dedicated LiPo bag, but an even safer solution is a metal box or a dedicated LiPo storage box. Just make sure the batteries aren’t stored in a completely airtight container — in the event of a fire, the gases produced need a way to escape, otherwise the pressure can rise to dangerous levels. I’ve noticed that some fellow pilots use metal ammunition boxes for this purpose, drilling a few ventilation holes in them before storing their batteries inside.
- Before every flight, it’s worth giving the battery a quick inspection. If it is severely swollen, damaged, punctured, has broken wires, or has cracked insulation, the battery should no longer be used. It would be frustrating if the power supply from the battery to the drone failed during flight — or, even worse, if the battery caught fire.
- It is also recommended to store batteries in a way that prevents their contacts from accidentally touching metal objects. An accidental short circuit can instantly cause a very high current and rapidly heat up the battery. Simple rubber bands can work perfectly well for this. By securing the wires against the batteries, they will stay neatly in place inside a battery storage bag or box.
- Quite recently, I also came across rubber caps for XT30 and XT60 connectors. These provide an additional layer of protection for the connectors.
Voltage sag
If you monitor the battery voltage shown on the OSD during flight (and you really should), you’ve probably noticed that when you suddenly increase the throttle, the voltage immediately drops, and when you reduce the throttle, it rises again. This phenomenon is known as voltage sag.
It happens because under heavy load, the battery has to deliver a very high current. Due to the internal resistance of the cells, some voltage is “lost,” causing the battery voltage to temporarily drop below what it would be at rest.
A small amount of voltage sag is completely normal. However, if the voltage drop becomes very large, it may indicate that the battery is aging and its internal resistance has increased, or that it simply isn’t capable of delivering as much current as your drone requires. By the way, if the voltage drops too low, a brownout can occur, causing the flight controller to reboot and the drone to temporarily lose both control and video in the goggles (if you’re flying low, the drone may crash, while at a sufficient altitude, it may have enough time to recover before reaching the ground).
This is exactly why you shouldn’t judge the state of your battery during flight based solely on the instantaneous voltage at full throttle. What matters much more is the voltage it recovers to once the load is reduced. By the way, new batteries usually show only a small amount of voltage sag, while worn batteries tend to show a much more noticeable drop.
Internal Resistance — IR
Each battery cell has a certain amount of internal resistance (IR). A new, high-quality battery will usually have low IR, but it increases over time. This is one of the best indicators for evaluating the condition of a battery. The higher the IR, the harder it is for the battery to deliver high current. During flight, this results in greater voltage sag, less power available to the motors, and more battery heating.
Many FPV battery chargers can measure internal resistance. They display the IR value of each cell separately, allowing you to monitor not only the overall aging of the battery but also to notice if one cell starts deteriorating faster than the others.
It’s important to understand that the absolute IR value isn’t as important as how it changes over time. Chargers from different manufacturers may show slightly different readings, so it’s best to evaluate a battery’s condition using the same charger every time. A simple battery log can be useful here, where you can regularly record the IR of each battery you own. If you notice that a battery’s internal resistance has doubled over several months and it also shows significant voltage sag during flight, the battery is probably approaching the end of its useful life.
By the way, as battery cell count increases (from 1S to 6S), the IR readings you typically see tend to decrease. So it can be perfectly normal for a new 1S battery to have an IR of around 20 mΩ, while a new 6S battery may show around 5 mΩ per cell.
Battery Lifespan
How long does a FPV battery last? There is no single answer. Some batteries are higher quality than others. One battery may lose a significant portion of its performance after 80 flights, while another may still be perfectly usable after 300 cycles.
The main measure of battery lifespan is the number of charge–discharge cycles. One cycle is considered a full discharge followed by a full recharge. In real life, however, things aren’t quite that simple. If one day I discharge a battery only to around 3.8 V per cell, then recharge it the next day and discharge it to 3.8 V per cell again, that doesn’t mean the battery has gone through two full cycles. Two such partial discharges would add up to roughly one full cycle.
Although every charging cycle causes some battery wear, in practice, how the battery is used has a much greater impact. If your goal is to wear out a battery as quickly as possible, you should:
- frequently discharge it to a very low voltage (the “practically empty” level from the table above — around 3.3 V per cell or even lower for LiPo);
- leave it fully charged for long periods (for example, 4.2 V per cell for LiPo);
- leave it in a hot environment (for example, inside a car during the summer or on a windowsill);
- regularly charge it at very high currents (for example, 2C or higher).
Manufacturers sometimes state that a battery can withstand 300, 500, or even more cycles. These numbers are achieved under laboratory conditions — batteries are charged at relatively low rates, below 1C, discharged under less demanding loads, kept at ideal temperatures, and not left fully charged for long periods.
FPV reality is quite different. In freestyle or racing drones, batteries are constantly subjected to high loads, heat up considerably, and during flight their voltage may briefly drop to 3.3–3.5 V per cell (perhaps even lower). All of this accelerates the natural aging of the cells.
In practice, you can use the following numbers as a rough guideline:
By the way, it’s worth knowing that LiPo batteries generally last longer than LiHV batteries, while Li-ion batteries generally last longer than LiPo batteries
How Much Do Batteries Cost?
When you first get into the FPV hobby, it’s not necessarily the cost of the drone itself or its parts that surprises you, but the price of batteries. When I bought my first drone, I bought only one battery. Since a single flight usually lasts just a few minutes, the first few times I went out flying, I had to head back home pretty quickly. It didn’t take long before I bought a few more batteries, so that whenever I went to a flying spot, I could at least get several flights in with batteries that were already charged.
Depending on the type of drone, a single battery can cost anywhere from a few dollars/pounds/euros to several dozen. Over time, it’s quite common for a FPV pilot to make this budget line cross the line of several hundreds on batteries alone.
| Battery | Indicative price; $/€/£ |
|---|---|
| 1S TinyWhoop | 5–10 |
| 2S TinyWhoop | 10–20 |
| 4S Freestyle | 20–35 |
| 6S Freestyle | 25–45 |
| 6S Li-Ion Long Range | 35–70 |
How Many Batteries Should You Have?
There is no single correct answer here as well. I, and I assume other pilots as well, choose to have enough batteries so that I don’t have to constantly wait for them to charge during a flying session (I’ve prepared a few Li-ion battery packs that I use to charge batteries while I’m flying, but since I charge at 1C or less, it still takes quite a while).
As a rough guideline:
- TinyWhoop — 6–12 batteries
- Freestyle — 3–8 batteries;
- Long Range — 2–4 batteries is usually enough.
Of course, it all depends on how long you plan to spend at the flying spot and whether you have a way to charge your batteries there.
Although, if your wallet is bottomless — go crazy. You can never have too many batteries. Just don’t forget how to store them safely.
Is It Worth Buying the Cheapest Batteries?
It may seem like a cheaper battery is always the better choice, but in practice, the opposite is often true.
Higher-quality batteries generally:
- maintain their voltage better under heavy load;
- generate less heat;
- lose their performance more slowly over time.
That’s why a more expensive battery will usually provide a better flying experience and last longer.
Recommended battery manufacturers/models
Of course, everyone has their own preferences here, but at least you can generally trust batteries from the most popular manufacturers.
- Tattu R-Line (premium)
- CNHL – Speedypizza Pro (premium)
- BetaFPV Lava series
- GNB
- Flywoo
- NewBeeDrone
- Dogcom (budget)
- CNHL – Speedypizza (budget)
- CNHL – Black (budget)
When Is It Time to Say Goodbye to a Battery?
Sooner or later, the time comes when a battery is done for and can no longer serve its purpose. In some cases, it simply loses part of its capacity; in others, it becomes unsafe to use. What matters much more is its actual condition.
Swelling
This is one of the clearest warning signs. If a battery has visibly swollen, it means that unwanted chemical processes are taking place inside it. You should stop using such a battery as soon as possible. Slight swelling doesn’t necessarily mean that the battery is about to catch fire, but it is a clear sign that its useful life is approaching the end.
And whatever you do, never try to puncture the wrapping and “deflate” the battery.
Voltage Sag
This is something you’ll only notice during flight. If the battery is fully charged and, right at the beginning of the flight, you give it more throttle and the voltage drops significantly and the drone loses power — or you simply see a “Land Now” warning on the screen — the battery is no longer capable of delivering the required current.
This is one of the first signs you’ll notice during flight that a battery is approaching the end of its useful life.
Internal resistance
This is perhaps more of an explanation for the previous point about voltage sag. As internal resistance increases, the battery finds it increasingly difficult to deliver high currents, generates more heat, and shows greater voltage sag during flight. If you notice that the internal resistance of the same battery keeps increasing, it is most likely gradually aging.
Chances are, you’ll notice this even without measuring internal resistance — the drone will become much more difficult to control, and flying it simply won’t be enjoyable anymore.
Cell Balance
If, after charging the battery, one cell consistently differs from the others and the charger finds it increasingly difficult to balance the cells (charging takes significantly longer), this may indicate that one of the cells is beginning to fail.
Reduced Capacity
If you used to get 5 minutes of flight time from a battery, but now you can barely get 2–3 minutes, even though your flying style hasn’t changed, the battery has most likely lost a significant portion of its capacity.
By the way…
It’s important to understand that you don’t need to throw away a battery simply because it’s old. Batteries with reduced capacity can still be perfectly usable for other purposes, such as powering FPV goggles. If a battery intended for racing can no longer “keep up” with the demands of aggressive flying, it may still be perfectly suitable for more relaxed flights.
Battery Disposal
Lithium batteries should never simply be thrown into household waste. They may still contain a significant amount of stored energy, so even a battery that is no longer being used can cause a fire. Before disposing of a battery, it is recommended to fully discharge it. You can use your charger’s Discharge mode or a dedicated battery discharger for this. Once the battery voltage is very low, it should be taken to an electronics or battery recycling collection point, where it can be properly recycled.
Although you can still find advice online suggesting that batteries should be discharged by submerging them in salt water, this method is considered outdated and is not recommended. It is much safer and more controlled to discharge batteries using equipment designed specifically for this purpose.
I’m not sure about disposal in other countries, other than my own (Lithuania) – but I guess it should be an universal process in most countries. I’ve requested a company which is responsible for electronic waste disposal – how to deal with old lithium batteries. In general their response was:
Before taking the battery to a recycling collection point, we recommend:
- covering its contacts with electrical tape to prevent a short circuit during transport;
- packing each battery separately so that it cannot come into contact with other batteries or metal objects;
- not disassembling, puncturing, crushing, or otherwise damaging the battery.
So, TL/DR – The Minimum You Should Remember
In short:
- Charge batteries only up to the maximum voltage allowed for their chemistry (the simplest way is to select the correct battery type on your charger — LiPo, LiHV, or Li-ion).
- Charge at 1C or less.
- Once fully charged, don’t leave a battery that way for more than 24 hours. Either fly it, or, if that isn’t possible, discharge it to storage voltage (around 3.8 V per cell).
- Stop using the battery before its voltage drops below the safe level.
- Store batteries in a cool place and avoid leaving them in direct sunlight.
- Use a LiPo bag.
- Regularly inspect batteries for physical damage.
The biggest and most common mistakes
- Leaving fully charged batteries for weeks.
- Flying until the battery is completely discharged.
- Charging batteries without using Balance Charge mode.
- Using damaged batteries.
- Buying the cheapest batteries based solely on their advertised C rating.
- Ignoring increasing internal resistance.
- Leaving batteries in a hot car.
- Mixing up LiPo and LiHV charging modes.
- Not storing batteries in a safe, fire-resistant location.
What do I use?
After writing all of that, I should probably finish by sharing what I personally use on a daily basis:
Battery chargers
| BetaFPV BT2.0 Battery Charger |
| My first charger was a 1S battery charger that came with my BetaFPV Meteor75 Pro tinywhoop. Right from the start, I knew I wouldn’t really use it as a charger because it only has two channels and doesn’t allow me to set the battery to storage voltage. But I still use it to this day as a quick battery voltage checker. |
| Vifly Whoopstor 3 |
| This charger was ordered just a few days after the first one. Charging only two batteries at a time? No, no, no. A long wait for the batteries to charge, just a few minutes of flying — and then you start all over again. The WhoopStor has six channels and allows you to charge six batteries at the same time. Since I sometimes feel like flying around the house as well, this is the charger I use the most. Would I replace it with something else? Not anytime soon. However, if I were buying my first 1S battery charger today, I would choose the GEPRC WooPower W63. Why? GEPRC allows you to configure the charging parameters for each channel independently. Sometimes, after flying my smallest BetaFPV Air65, I already want to prepare its batteries for long-term storage while at the same time charging the larger batteries for my BetaFPV Meteor75 Pro. But that’s definitely not a dealbreaker that would make me buy another charger (especially since I have other “accessories” for charging 1S batteries — see below). |
| SkyRC B6Neo |
| My first charger for larger batteries. Extremely small and portable, with the ability to check battery voltage and measure internal resistance — everything you need when starting out. Most importantly, it can be powered not only through XT60 or DC5.5, but also via USB-C PD 3.0, so I didn’t need to change anything on my workbench. Everything I needed was already there. Over time, having only one channel became a bit limiting. I don’t have that many batteries, so I charge them not only at home but also at the flying spots. Would I replace this charger with something else? Definitely not. I used it every day back then, and I still use it every day now. And with a few additional accessories, it’s even more useful than it was in the beginning. |
| HOTA F6 |
| This is my current workhorse. Four channels, each of them configurable independently. Admittedly, it may not be the right choice for everyone because it can only be powered from DC (XT60 connector). But since I had an old 135 W laptop power supply lying around at home, replacing its connector solved the power supply problem. For those who find this setup unsuitable, there is also the F6 Ultra model, which already has built-in AC power support. It also has USB-C and USB-A ports for charging or powering other devices. I don’t use them very often because I already have several dedicated charging cables on my desk. By the way, quite recently, during a storm in the countryside, the power went out and I actually got to use this feature. I powered the charger from a Li-ion battery pack I had with me and used its USB output to charge my phone. A pretty niche use case, but at least I got to do a little more scrolling before going to sleep. |
| SkyRC OSH |
| When I saw the OSH 6-Port 1S Lithium Battery Charging Hub, I bought it without hesitation. For just €10, the ability to turn my B6neo into a six-channel charger for 1S BT2.0 batteries seemed very, very appealing. And indeed — it has made my life much easier. The WhoopStor’s downside of not being able to charge batteries using different modes has been solved, albeit indirectly: one mode on the WhoopStor, another on the OSH. However, this little gadget does have one downside. It isn’t causing me any problems yet, but I’m sure it will in the future. For the charger to correctly detect the number of batteries being charged (it sees them as if they were the individual cells of one larger battery), you have to move a tiny jumper. It’s very small and completely unprotected, so I suspect I’ll eventually have to find something to replace it with. Not only does it look exposed and very fragile, but it also doesn’t stay in place particularly securely. The B6neo goes everywhere with me because I can simply grab it and throw it into practically any pocket of my backpack. This little accessory, however, is something I can’t just toss anywhere quite as confidently — specifically because of that tiny jumper. |
| VIFLY 1S Series Charging Board |
| Tai naujausias įkroviklis mano kolekcijoje. Atsidūrė labai netikėtai, netyčia jį užmačius Vintede. Kaip ir SkyRC OSH – jungiamas prie didesnių baterijų kroviklio XT60 ir balansavimo jungčių. Norėtusi jį įvilkti į kokį 3D printeriu atspausdintą dėklą, bet čia jau ir taip gero daikto mini patobulinimas. Skirtingai nei OSH – naudojamas ne jumperiuk’as, bet sukiojama patogi rankenėlė, kuri tikrai tvirtai laikosi. Šis priedėlis išplėtė vienu metu kraunamų BT2.0 baterijų skaičių iki 18. Ženkliai daugiau nei mano dabartinis poreikis. Jei reiktų rinktis tarp šio ir SkyRC OSH – rinkčiaus šį. Jis nors ir brangesnis nei OSH, bet pigesnis nei Whoopstor. This is the newest charger in my collection. I came across it quite unexpectedly after spotting it by chance on Vinted. Just like the SkyRC OSH, it connects to the (2nd hand market app in Europe) XT60 and balance connectors of a charger designed for larger batteries. I’d like to put it into some kind of 3D-printed case, but that would really just be a small improvement to something that’s already good as it is. Unlike the OSH, it doesn’t use a tiny jumper. Instead, it has a convenient rotary knob that stays firmly in place. This accessory has increased the number of BT2.0 batteries I can charge at the same time to 18. That’s significantly more than I currently need. If I had to choose between this and the SkyRC OSH, I’d choose this one. Although it’s more expensive than the OSH, it’s still cheaper than the WhoopStor. |
Batteries
Real ZOO here
| 1S LiHv batteries (BT2.0) | • BetaFPV LAVA 2 580 mAh 95C — my main batteries for the Meteor75 Pro tinywhoop. They’re my main batteries simply because they’re the newest. Compared with the previous LAVA series, they can deliver higher current for longer, and the overall flight time is almost a minute longer. • BetaFPV LAVA 550 mAh 75C — my main batteries from last year. Compared with the standard batteries, they provide at least one minute of additional flight time. • BetaFPV 550 mAh 40C — the first standard 1S batteries that came with my Meteor75 Pro drone. I’ll be disposing of them in the near future. • BetaFPV LAVA 2 320 mAh 95C — my main batteries for flying the Air65. • BetaFPV LAVA 260 mAh 80C — since they’re still fairly new, I’m also using them extensively with the Air65 this year. |
| 3S Lipo batteries (XT60) | CNHL Black series 2200mAh 40C – This is my main battery for powering various equipment, most often my FPV goggles. Sometimes I use it to power a SpeedyBee adapter, so I can configure my drone in the field without a computer. I haven’t tried using it with a drone yet. I actually bought it as a battery for powering a spot welder used to build battery packs. |
| 4S LiPo batteries (XT30) | Tattu R-Line V1 850 mAh 95C and Tattu R-Line V5 850 mAh 150C — excellent, high-end batteries for a cinewhoop drone. Although the V5 isn’t the latest generation like the V6, both the current output and capacity are more than enough for a fun 7–8-minute flight. |
| 6S LiPo batteries (XT60) | • Tatttu R-Line v5 1480mAh 150C , • Tattu FunFly 1300 mAh 100C , • CNHL Speedy Pizza PRO 1500mAh 150C I haven’t noticed much of a difference between these batteries. But to be fair, with my 5-inch freestyle drone, I don’t push them anywhere near their limits. |
| 4S/6S Li-Ion battery cell packs | • 6S2P (8000 mAh, 10C) built from BAK N21700CGP 21700 4000 mAh cells. This is a battery pack I built myself for charging other batteries while traveling. During a trip to Croatia, I used this pack to charge my camera drone batteries on the road. I also use it when testing a newly built 6S drone on the workbench. Currently, I’m also using it for test flights with my 10-inch drone. My next purchase will probably be either higher-discharge tabless cells to build another battery pack myself, or a factory-made 6S2P or 6S4P battery pack. • 4S2P (5000 mAh, 8C) built from Samsung 25R 18650 2500 mAh cells. This is an additional power bank — sometimes I use it to power my FPV goggles, and sometimes to charge 1S batteries at the flying spot. |
Sources
- https://www.evlithium.com/Blog/18650-battery-voltage-guide.html
- https://www.ersaelectronics.com/blog/18650-battery-voltage-a-complete-guide
- https://trydantech.com/newsroom/what-are-tabless-battery-cells-a-technical-deep-dive
- https://oscarliang.com/gnb-6s-lihv-lipo-batteries/
- https://www.molicel.com/wp-content/uploads/INR21700P45B_1.2_Product-Data-Sheet-of-INR-21700-P45B-80109.pdf
- https://genstattu.com/bw/
- https://chinahobbyline.com/blogs/news/the-best-way-to-charge-and-storage-your-lihv-battery
- https://www.grepow.com/blog/lipo-battery-vs-lihv-battery-what-is-the-difference.html
- https://www.grepow.com/blog/what-is-the-voltage-of-a-lipo-battery.html
- https://www.batteryuniversity.com/article/bu-303-confusion-with-voltages/
- https://www.batteryuniversity.com/article/bu-409-charging-lithium-ion/
- https://4-max.co.uk/pdf/HOTA/HOTA-F6-User%20Manual.pdf
- https://news.samsungsdi.com/global/articleView?seq=322
- https://www.battery-germany.de/wp-content/uploads/2021/02/LF50K3.2V-50Ah-Product-SpecificationVersion-D.pdf
- https://www.instagram.com/p/C8cskA8tj2q/?img_index=4&igsh=MWp2NWx2OGNmY2Zmdw%3D%3D
- https://blog.skyrc.com/using-the-cc-cv-method-to-charge-lipo-batteries/
- https://oscarliang.com/parallel-charging-multiple-lipo/
- https://www.youtube.com/watch?v=lZKoW_ekAu0
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