Lithium-polymer batteries, also known as LiPo batteries, are the only batteries used in Rc Drift today, thanks to their small size, light weight and, above all, high performance.
Watch our video on battery use and maintenance
WHAT DO THE NUMBERS ON A LIPO BATTERY MEAN?
The numbers on Lipo batteries help you understand their properties. There are three markings that indicate the most important parameters of your battery.
A Lipo cell has a nominal voltage of 3.7 V (or 3.8 V in the case of HV batteries). You'll often find higher values, as on the battery above: 14.8 V means that there are four cells connected in series, as the voltage adds up. In the modelling world, you'll often find 2s batteries to indicate the presence of 2 cells, 3s batteries for 3 cells, 4s batteries for 4 cells and so on. In Rc Drift, 2s batteries are the only ones used.
Battery voltage affects the speed of the electric motor, and will therefore determine the speed of your radio-controlled vehicle. For brushless motors, power is measured in kV (RPM per volt). For example, a motor with a power of 3,500 kV will turn at 3,500 rpm for each volt, so with a 2S Lipo battery it will turn at 25,900 rpm, with a 3S battery at 38,850 rpm, and so on.
To help you, here's a small summary table:
|Designation||Number of cells||Voltage|
|1S||1||3.7V or 3.8V for HV cells|
|2S||2||7.4 V or 7.6V for HV|
|3S||3||11.1 V or 11.4V for HV|
|4S||4||14.8 V or 15.2V for HV|
|5S||5||18.5 V or 19V for HV|
|6S||6||22.2V or 22.8V for HV|
|7S||7||25.9 V or 26.6V for HV batteries|
HV (High Voltage) batteries
These are the new-generation batteries that deliver greater power and capacity. You charge your battery at 8.7 V instead of 8.4 V. Ideally, you should have an LI-HV (Lipo High Voltage) compatible charger, but it's not compulsory. You just won't charge them fully, but you won't damage them.
A battery's capacity determines how long you can use it before it discharges. It's expressed in milliamperes (mAh). The higher the value, the greater the car's range. In Rc Drift a 4000mah with the electronics of the RTR MST kit, you'll be able to drive for around 20 minutes.
The C value is the maximum capacity of your battery without danger of continuous discharge. For example, on the battery above, 45C means you can discharge the battery at up to 45 times its capacity continuously, i.e. 4000 mAh 45C = 4.5A x 45 = 202.5A max continuous discharge. Rising above the max. continuous discharge rate can, at best, lead to faster deterioration of the battery and, at worst, cause the battery to catch fire. Always choose a discharge rate well above your maximum continuous discharge, as this may vary according to terrain, tire size or vehicle weight. (For RTR MST kits, 45C is more than sufficient).
HOW DO I TAKE CARE OF MY LIPO BATTERY?
PRECAUTIONS TO TAKE
Lipo batteries offer drifters power and autonomy, but these advantages come with a few drawbacks. If a Lipo battery is damaged, as lithium is highly reactive in contact with water or humidity, it can release toxic gases and cause a fire. Nevertheless, this type of battery presents no danger as long as you follow certain safety instructions. (In the end, you have almost the same thing in the smartphone you're holding in your hands).
- Immediately dispose of a lipo battery that has begun to swell, is damaged or punctured, by handing it over to a center authorized to handle hazardous products.
- Do not attempt to charge a damaged battery.
- Do not leave the battery in a vehicle or in direct sunlight.
- If your lipo battery catches fire, do not extinguish it with water, but rather with sand or an electrical fire extinguisher.
CHARGING A LIPO BATTERY
New Lipo batteries are always charged to 40% of their total capacity, as manufacturers believe this is the best way to store them for long periods. An initial charge is therefore necessary before use. Do not use the Fast Charge function for the first few charging cycles, and do not use a battery charged to less than 50%. This is to preserve battery life and performance. As a general rule, Lipo batteries should never be discharged below 3.2 volts per cell, otherwise they may be damaged. Below this voltage, the battery's chemistry is unlikely to recover, making it impossible to charge your battery. In practice, setting your lipo cut-off on the esc to 3.5v/cell is even better. In the case of RTR kits, the drive is already programmed correctly.
Before charging a Lipo battery, remove it from the radio-controlled vehicle and inspect it for deformation or cuts. Never place the battery on a flammable surface (carpet, wood, etc.) or inside a vehicle with the engine running. You should also keep an eye on the battery throughout the charging process. The best way to charge safely is to carry a fireproof charging bag, and never leave home or any other place with a battery charging.
Before charging a Lipo battery, remove it from the RC vehicle and inspect it for deformations and cuts. Never place the battery on a flammable surface (carpet, wood, etc.) or inside a vehicle with the engine running. You should also keep an eye on the battery throughout the charging process. The best way to charge safely is to carry a fireproof charging bag, and never leave home or any other place with a battery charging.
HOW TO SET UP MY CHARGER :
A LiPo battery is generally charged at 1C, i.e. at one time its capacity. Example:
- For a 4000mAh (4Ah) LiPo battery, the charging current to be programmed on the charger will be 4A.
- For a 4500mAh (4.5Ah) LiPo battery, the charging current will be 4.5Ah.
- For a 5000mAh (5Ah) LiPo battery, the charging current will be 5Ah.
It will take approximately 1 hour to charge the battery.
STORING A LIPO BATTERY
The ideal place to store your Lipo batteries is ventilated, cool and dry, with a temperature between 5°C and 27°C. Batteries should be stored at half-charge (i.e. around 3.8 volts per cell): modern chargers have a "storage" function to obtain the storage voltage. During transport, the ambient temperature should be between 5°C and 50°C, away from direct sunlight. If you're not going to be riding in the next week, leaving your batteries fully charged will cause them to swell in 90% of cases. Conversely, leaving them fully discharged for too long will cause them to drop below 3.2V, and you'll be able to throw them away as they can't be recharged (there are techniques for restarting them, but we won't give them to you as they're far too risky, with a high risk of fire). Store your batteries in a fireproof charging bag