This Lithium Polymer Battery has different performance and safety specifications from our Lithium-ion batteries. Please follow all the performance and safety guidelines below.
Although they are used in everyday consumer electronics devices (phones, laptops. etc.) lithium polymer (LiPo) batteries have a high energy density and must, like all batteries, be treated with care to ensure safe operation and a long lifespan.
- Avoid discharging below 3.3 V/cell (13.2 V) and never below 3.0V/cell (12 V)
- Never charge over 4.20 V/cell (16.8 V)
- Do not puncture, crush, cut, or disassemble
- Discontinue use if the battery swells or changes appearance*
- Do not burn or expose to temperatures above 50°C (122°F)
- Always use a lithium polymer compatible balance charger
- Do not leave unattended while charging
- Do not exceed maximum charge (15 A) or discharge (90 A**) rate
- Do not pick up by discharge leads, always handle by gripping the battery body
*See Lithium Polymer Battery Puffing/Swelling section below for more information.
**See Discharging section below for more information.
Additional General Lithium Polymer Battery Information and Safety Resources:
A Guide to Understanding LiPo Batteries
Lipo (Lithium) Battery Safety Guide
Always use a lithium polymer compatible balance charger when charging, attempting to use another type of charger will damage the battery. Make sure to keep it away from flammable materials and monitor the battery as it charges, discontinue charging if it becomes hot, swells, or changes in appearance.
This battery can be safely charged at up to 15 A, which will bring it back up to full charge in less than an hour. However, we recommend charging at 10 A (full charge in a little over an hour) at most regularly, in order to maximize capacity and lifespan. We strongly recommend balancing the battery at every charge to keep all cells at the same level of charge, but this can also be done every few cycles if quick charging is a priority.
Our Lithium Battery Charger is recommended for use with this battery.
Once charged, connect the XT90 discharge plug to your vehicle, and the battery is ready to use. This battery does not have a built-in battery management system to prevent overdischarging. The battery voltage must be monitored to prevent discharging below the minimum safe voltage level of 12 V.
The battery can sustain a constant discharge of up to 90 A, and up to 120 A in short bursts of a few seconds. Make sure to never short the battery discharge plug or plug it into a circuit that may be shorted.
Note that the maximum safe discharge rating is dependent on adequate cooling to keep the battery below 50°C. If used in an enclosed space without airflow, constant current draw must be decreased appropriately to keep the battery at a safe temperature. For example, in a BlueROV2 we recommend keeping full throttle thruster bursts at 100% gain to no more than 30 seconds each to keep the battery at a safe temperature and allow it to cool.
Avoid storing the battery at full charge (16.8 V) for longer than 6 hours at a time. If the battery will not be immediately used (within the same day), it should be stored at about 50% charge, or 3.7 V/cell (14.8V). Limiting the amount of time the battery stays at full charge significantly improves battery health and usable lifespan.
Charge will be lost over time when the battery is stored, and care must be taken to ensure long-term storage does not damage the battery. Storage temperature should always be below 50°C (122°F), and the lower, the better. It should be periodically checked and charged to keep each cell above the 3.3 V minimum.
Lithium Polymer Battery Puffing/Swelling
The improper use or maintenance of lithium batteries accelerates electrolyte decomposition in the battery, leading to a buildup of excess gas within the battery. This gas buildup can make the battery appear “puffy” or “swollen”. Follow these safety guidelines if you notice your battery begins to change appearance:
- Very slight puffing or swelling of the battery is not ideal but is generally safe to continue use in most cases. Slight puffing and swelling are strong indicators that the battery is being stressed and more care should be taken to maintain good battery health by following our guidelines for:
- Storing the battery at 50% charge when not in use
- Proper charging
- Avoiding overdischarging or exceeding the maximum continuous discharge rate
- Keeping temperature below 50°C (122°F)
- Significant puffing or swelling is very dangerous. If your battery appears significantly puffy or swollen immediately discontinue use and dispose of it properly.