There have been a lot of questions about LiPo batteries lately. I decided to write an article about charging, using and selecting LiPo batteries.
For example, consider a battery ZIPPY Flightmax 1000mAh 2S1P 20C
Anything up to 1000 is the manufacturer's name or trademark.
1000mAh is the capacity of the battery.
2S1P- 2S is the number of batteries in the assembly. Each battery has a voltage of about 3.7 volts, so the voltage of such a battery is 7.4 volts. 1P is the number of builds. That is, if you take 2 identical batteries, connect them with electrical tape and solder the power wires in parallel (plus with plus, and minus with minus), then we will get a doubling of the capacity, such a battery is designated 1000 2S2P and actually equals 2000 2S1P in operation. Usually only single assemblies are used, so 1P is not spoken or written.
20C- maximum discharge current, measured in battery capacities.
To calculate how many LiPo can deliver amps when loaded with an engine, you need to multiply the Capacitance by the number of C and divide by 1000 (since the capacitance is indicated in milliamps / hours). The maximum current of this battery will be 20 amps. For 2200 20С - 44 amperes, 1200 30С = 36 amperes and so on.
But, this is theoretical, in reality now only expensive batteries give out the declared currents. For inexpensive ones purchased from China, it is necessary to focus on 70-80% of the maximum current, and during a long flight at full current output, even 50% of the declared one.
Charging LiPo batteries
LiPo batteries are charged with a current of 1C, this is a gentle charge, often charging currents of 2-5C are indicated on the battery itself. But, this is only when you are in a hurry, for example - in flight.
The nominal charging current of the battery in question from the previous paragraph is 1 Ampere. For a 2200 battery, it will be 2.2 amps, and so on.
You can read about chargers (chargers) in the article
The computerized charger balances the battery (equalizing the voltage on each cell of the battery) during charging. Although it is possible to charge 2S batteries without connecting a balance cable (white connector in the photo), I highly recommend always connect the balancing plug! 3S and large assemblies only charge with the balance wire connected! If you don't connect and one of the cans draws more than 4.4 volts, then an unforgettable fireworks display awaits you!
You can protect yourself and charge in special packages - they are non-combustible and are specifically designed to reduce harm in the event of a LiPo battery fire.
You can buy a fireproof battery charging bag.
There are also fireproof bags for storing LiPo batteries.
You can buy such a bag for LiPo. I have one, I carry it in the field.
We continue the story about charging LiPo batteries.
The battery charges to 4.2 volts per cell (usually a few millivolts less).
"Storage" mode for LiPo
On a computerized charger, you can put LiPo into storage mode, while the battery will be recharged / recharged to 3.85V per cell. Fully charged batteries will die if stored for more than 2 months (maybe less). Verified by personal experience. They say that they are completely discharged too, but for a longer period.
I store batteries in a plastic case. It's comfortable. A friend keeps and wears in the field in the aforementioned packages. LiPo is an ordinary battery and if you do not close the contacts and do not break through it, then it will not bring any trouble during storage and transportation.
Operation of LiPo batteries
Discharging a LiPo battery below 3 volts per cell is not recommended - it can die. The engine controllers have the function of shutting down the engine when this condition occurs. I use . It connects to the balancer connector and, as soon as it squeaks, it's time to land.
When the motor draws more current than the battery can supply, LiPo tends to swell and die. So this must be strictly monitored! Use for control. It is enough to measure once for the motor with each available screw and just know how many amps the motor eats on this type of screw.
During operation, there is one more nuance - our battery is 1000mAh 20C. The idea is to give 20A. Motors usually allow you to exceed the recommended currents by 20%, however, I exceeded by 80% :)
In reality, as I wrote above, the batteries do not hold the maximum current output very well. For example, my 2200 20C gives a current of 44A in just 2-3 minutes, then there is a voltage drop, although according to calculations it is obliged to give at least 5 minutes. And the new Zippys do not give the declared maximum current at all.
So when choosing a LiPo battery, we look at the maximum current declared for the selected engine and add a reserve. So for a motor that eats 8-12A, our 1000mAh 20C is quite suitable, but for 16-18A I would choose either with a higher current output, for example 25-30C, or take a larger capacity, for example 1600 20C.
By the way, nano-tech batteries with a current output of 80C have now appeared.
At the moment of writing this article, lithium-polymer batteries (LiPo) are the leaders in current output, and therefore modelers of all countries gladly switched to them. What is a LiPo battery, it is a special polymer that is saturated with a lithium-containing solution.
Lipo Advantage:
- For example, LiPo with the same weight is able to give off more energy than NiCd by 4-5 times, and NiMH by 3-4 times.
- The number of working cycles is 500-600. In two years, the battery loses only ~ 20% of its capacity.
- There are two types - fast bit (Hi) and regular. If, for example, the notation contains 3C 1000mA, this suggests that such a battery is capable of delivering current up to 3A without harm to itself, and if 40С 1000mA, then a current of 40A is not a problem for such a battery. Can you imagine how many amps a battery can deliver? 40С 3S 5000mA, it can turn the starter of a real car, just connect it in parallel with a standard lead battery and make very short pushes so that thin wires do not burst into flames!
- Ordinary Liposhki (the common name LiPo) are used in electronics that do not require large discharge currents, mobile devices, tools, and the bokeh (C) is not used in the designation of such. The letter (S) in the designation indicates how many cans are in the battery.
What are LiPo afraid of:
- High battery temperature is much worse than low voltage. When discharging, the battery should not be allowed to heat up to more than 60 ° C (spontaneous combustion or explosion will occur!)
- When used outdoors during the cold season, be sure to keep the batteries warm before use.
- Swelling of the battery, as a result of chemical processes inside it, as a result of degradation, physical aging, and a decrease in capacity.
- If the sufficiently soft shell of the battery is broken, or its shape changes, fire and even an explosion are possible! Even if it seems that nothing happened to the battery after the plane crash, but an emergency can occur during subsequent charging!
Discharging LiPo:
- The minimum voltage of a discharged battery bank should not fall below 2.5V, but it’s better not to take risks and not drop below 3.3V, otherwise salt deposits begin and the number of cycles decreases, and an internal short circuit is also possible and, accordingly, will cause severe heating, fire and even explosion. Therefore, it is imperative to use sound indicators, which emit a loud squeak when the battery approaches the minimum voltage values in any of the cans.
- For brand new batteries, the first three discharges should be done with a current of 3-5C. This will allow the elements to be reactivated (to develop an inhibitor), equalize the voltage across the banks and gain full capacity.
Lipo Charging:
Carefully! Personally, I always charge batteries outside the house, which I recommend to everyone, this is due to a large number of spontaneous combustion!
Lipo Storage:
- Storage temperature from 5 to 28°C, according to other sources from 0 to 10°C. Modellers believe that storing batteries in the refrigerator is the best option and that way they will last much longer.
- The voltage on the banks is 3.7-3.85V, which is ~ 40% of the full charge, it is with this voltage that LiPo batteries are supplied by manufacturers. Smart storage has a LiPo switch to storage mode. When stored with a different level of charge, they lose their capacity much faster, which is then not restored.
- LiPo batteries age even when not in use, so there is no need to buy spare batteries. When buying, be sure to check the production date, because a two-year-old battery has already lost at least 20% of its capacity.
A portable charger is a way to charge LiPo batteries in the field for longer flight times. Below we will look at ways and solutions for charging batteries in the field. I think it's cheaper and easier than buying a bunch of batteries.
When I go flying, I can easily drain more than 20 batteries in a day while flying a racing car. You can, of course, buy as many batteries as you need for a flight session, but I believe that Charging in the field is a more economical and practical solution.
What is included in the field (portable) charger
- Charger iSDT SC-200 (banggood)
- 1 LiPo battery 6S 10000mAh (aliexpress)
- XT90 to XT60 adapter (banggood)
- Parallel Charging Board (banggood)
- Voltmeter (banggood)
Let me tell you why I like field charging so much and why it is more profitable.
Field charging is cheap
As you probably already know, it is not recommended to leave a fully charged LiPo in storage, this leads to a deterioration in battery performance, and most importantly, it is unsafe, since ignition is possible.
Therefore, if you have charged extra batteries and do not have time to fly them off, you will have to discharge them with a charger.
But in the field assembly, you can “put” the charge back into a large donor battery or recharge dead batteries, as well as charge goggles or a helmet.
Portability
The weight of a field charge is lower than 18 batteries, and it takes up much less space.
- Total weight of 18 4S approximately 3.4kg
- Weight 8 4S + 1 large + memory + parallel board = 1513g + 1211g + 451g = 3.1kg
The overall weight savings is certainly not that big, but space savings play a bigger role here. 6S is slightly larger than four 4S batteries.
Field charging is safer
Since instead of 18 batteries, we have 8, in fact, the chance of ignition or any other dangerous malfunction is reduced by 2 times.
Cons of a field charger
Any thing has its drawbacks, in our case there are several of them:
- You need to buy a new LiPo charger that will support connection as a LiPo battery source. If you already have it, then this minus is excluded.
- This charge is relevant for those who fly a lot. If you discharge less than 15-20 batteries per session, then it will not be so attractive for you.
- To ensure parallel charging, your batteries must be at the same voltage level. This means that you have to pay extra attention to stress while flying and decide when you should land. This is easy to do if you have an OSD that displays the amount of current drawn.
Selecting a charger for field charging
The charger needs one that can operate on direct current. The input voltage range must be wide so that you can connect any battery as a power source.
I especially like the iSDT series (SC608, Q6, SC620) for charging LiPo batteries in the field due to their compact and lightweight designs. They support 9V-32V input and come with an XT60 connector that allows you to use LiPo batteries as a power source. They are also great for everyday charging.
Selecting a Power Source for Field Charging
For such charging, you will need some kind of capacious power source, below is a table with options:
| Name | High capacity LiPo batteries | portable generator | Deep discharge battery | Solar Panel Generator |
| Fuel | rechargeable | gasoline/diesel | rechargeable | Rechargeable - sun |
| Voltage | 11.1V - 25.2V (3S-6S) | Miscellaneous - AC and DC | 12V | Miscellaneous - AC and DC |
| Capacity | Low (10Ah – 16Ah+) | High | High (20Ah – 120Ah) | Medium |
| Weight | Light (1Kg – 2Kg) | heavy | Heavy (5Kg – 35Kg) | Medium |
| Price | Inexpensive | Expensive | $50 – $300 | Expensive |
For charging, some use a car battery, but this is not recommended, as you will simply ruin it. Instead, deep-cycle batteries should be used.
If you have a lot of batteries and you always fly with someone, then a great solution would be to buy a generator running on gasoline or diesel fuel. They are powerful and often provide constant current that is compatible with a wide range of chargers. But they are expensive and noisy, unlike other power sources.
Solar generators are a great option if there is a lot of sun where you live, or just a sunny day during flights.
I prefer to charge with a large Lipo battery - it's easy and cheap.
Any beginner has a question: What is LiPo and what it is eaten with. Let's try to figure it out.
After reading it, beginners began to ask questions about LiPo, which was the reason for creating the article.
1.What is a LiPo battery?
It often happens that a person does not want to look for anything and immediately asks questions. I won't move the text. Read.
http://bit.ly/YgKh2X
Lipo acc. must be carefully chosen for the model.
Any LiPo acc. has a label. For example Turnigy 1600 mah 3S 30C where,
Turnigy - manufacturer
1600 mah - battery capacity
3S - number of cans (1 can 3.7v)
30C - current output
1C - one battery capacity. For our example, 1600 ma (or 1.6A) A is ampere
For the provided battery, we get: 30 x 1.6A = 48A
The RC system of the model that uses this acc. , should have a peak current in the electric circuit of less than 48A, preferably with a margin. (No more than 40-45A)
If this condition is not met, the battery will be killed.
An alarming sign will be its swelling. Such batteries can be returned to their original state by putting them in a refrigerator or basement / cellar; however, the functionality will be reduced. After such procedures, you need to do a couple of discharge-charge cycles.
I want to emphasize that LiPo is a dangerous thing and must be handled with care.
What not to do:
- damage the outer shell.
- heat.
- strongly discharge (below 3v.)
- charge with high currents.
2.How to charge?
To charge LiPo batteries, special chargers (chargers) are used.
It is highly recommended to use a charger with balancing capability.
Any LiPo acc. (2S and above) has 2 wires: 1) Power (red "+" and black "-")
2) Balancing.
A balancing wire is needed to evenly charge all the cans of the battery.
Modelers attach a tweeter voltmeter to the balancing wire to prevent discharge below the threshold.
LiPo batteries can be charged with 1C current. For a long life of your battery, you need to use a charge current of 0.4-0.6C. When choosing such a current, the battery will live longer (aging will progress less).
But I must indicate that there are batteries with a charge current of 2C or 5C. It will be indicated on the package.
Consider an example: Turnigy 1600 mah 3S 30C
Current 1C is 1.6A, but optimally for a battery, you can take a charge current of 1A.
The battery will be charged longer than with a current of 1.6A, but the service life will be longer.
If the charge current is more than 1C, then the battery may explode and there will be a fire.
Most advanced chargers have different LiPo charge options.
charge charge
discharge discharge
balance
storage
You need to select the number S of your battery, set the current strength - A and wait.
3.How to store?
Batteries must be stored 60% charged (3.8v per cell)
If stored at 100% charged or discharged for a long time, the battery will die/swell.
Proper storage of LiPo requires:
- Keep away from direct sunlight
- Temperatures from +18 to +5 are recommended (some modelers keep them in the refrigerator)
- Store in special bag or fireproof box.
- Put the battery in storage mode.
The article was written for a group in VK RC reviews
In this article, based on the recommendations of many mini quad pilots and racers, we will show you some great LiPo chargers. Selected chargers are reliable, easy to use and versatile.
Portability is another criterion that is important for mini quad pilots. in the field, too, sometimes you need to charge the batteries.
Other popular components for racing copters can be found by the tag "".
iSDT Series Chargers
iSDT Q6 Plus 300W
- Buy at Banggood | Amazon | GetFPV | RDQ
- Overview
iSDT SC-608 150W
- Buy at Banggood | Amazon
- Overview
iSDT D2 200W
Without a doubt, iSDT chargers are very popular in our group. There are 3 options with different maximum power, they will suit most pilots. The color screen user interface is easy to use. For the indicated power, they are quite compact.
All three chargers are portable and easy to use in the field. However, these are relatively new chargers, so make sure you have the latest firmware, with all the fixes and improvements. Here .
A small drawback of these chargers is the lack of a power supply. It must be purchased separately. For example, like this.
On ebay, I bought an inexpensive and lightweight laptop power supply (100 W), it is convenient to take it with me on trips. Due to the wide input voltage range, a lot of different power supplies will fit. The output jack can be slightly modified to add an XT60.
D2 is essentially two chargers in one case, it can charge 2 different batteries at the same time, or you can connect 2 different parallel charging boards to it. In addition, it has a built-in power supply so that it plugs directly into a power outlet.
Update (August 2017). Models SC608 and SC620 are no longer in production. They can still be found on sale, but there will be no more firmware updates. IMHO, it still makes sense to take them.
| SC608 | Q6 | SC620 | D2 | |
| Price | $50 | $60 | $70 | $140 |
| Power, W | 150 | 300 | 500 | 200 x2 |
| Max. charge current, A | 8 | 14 | 20 | 20 x 2 |
| built-in power supply,supply voltage | No | No | No | Eat |
| Weight, g | 110 | 119 | 289 | 510 |
SkyRC iMAX B6 Mini
- Buy at Banggood |AliExpress
Simple, budget charger. B6 Mini is an updated version of the old and well known B6 which was one of the most popular chargers. There are a lot of fakes out there, so make sure you get the original.
| Price | $40 |
| Power, W | 60 |
| Max. charge current | 6A |
| No, 11 - 18 V | |
| Weight, g | 233 |
SkyRC Q200
- Buy at Banggood | Amazon |AliExpress
The main feature of the SkyRC Q200 is 4 independent channels, i.e. it is equal to 4 separate chargers. This means you can charge 4 different batteries at the same time! It's just great, especially for those who do not want or cannot charge several batteries connected in parallel. Well, or if the batteries with a different number of cans.
It has a built-in power supply, as well as a DC input, i.e. it can also be used in the field. The disadvantage is the weight of about 1.3 kg.
You can even connect this charger to a computer or smartphone to control it and control the charging process.
Turnigy Reactor 300W
The Reaktor 300W has a built-in power supply as well as a DC input. This is definitely one of the most reliable chargers out there.
Don't like parallel charging boards? Then pay attention to SkyRC E4Q! This is an inexpensive 4-channel charger. Perfect for charging goggles/helmets.
It has an XT60 input, and due to its small size and weight, it is perfect for working in the field.
| Price | $55 |
| Max. Power, W | 4 x 50W |
| Max. charge current | 5 A |
| Built-in PSU, supply voltage | no, 11 - 26 V |
| Weight | 280 grams |
Hope these tips are helpful. We will keep an eye on new devices and try to keep this list up to date. Write if you have any questions.
History of measurements
- July 2017 - the first version of the article
- July 2018 - removed SC620 (out of production), added SkyRC E4Q and iSDT D2
