What are the differences between low-voltage and high-voltage lithium polymer batteries?
1. Main Difference: Voltage Platform and Energy Density
Low-voltage version: Typically refers to ternary lithium batteries with a 3.6V/3.7V voltage platform. Its full-charge cutoff voltage is generally 4.2V, and its discharge cutoff voltage is approximately 2.75V-3.0V.
High-voltage version: Typically refers to ternary lithium batteries with a 3.8V/3.85V voltage platform. Its full-charge cutoff voltage is higher, generally 4.35V or 4.4V, and its discharge cutoff voltage is also approximately 2.75V-3.0V.
Key Impact: At the same capacity (1000mAh), the high-voltage version, due to its higher voltage platform, delivers more actual electrical energy (Wh) according to the formula "Energy = Voltage × Capacity," providing a longer single-charge usage time for devices.
2. Applicable Devices and Charging Requirements
Low-voltage version (4.2V cutoff): Suitable for devices with traditional designs whose charging management ICs (chips) only support a 4.2V full-charge cutoff voltage. Using a low-voltage battery in a high-voltage charging circuit may result in insufficient charging and incomplete capacity utilization.
High-voltage version (4.35V/4.4V cutoff): Requires the device's charging management IC to support a higher cutoff voltage. Using a high-voltage battery in a device that only supports 4.2V charging will prevent the battery from being fully charged, significantly reducing its usable capacity. Conversely, using a high-voltage charger to charge a low-voltage battery can lead to overcharging, posing a safety risk.
3. Materials and Cycle Life
Differences in voltage platforms stem from adjustments to the cathode material formulation, thus affecting cycle life.
Low-voltage version: The cathode material formulation is more mature, resulting in relatively better cycle stability. Under standard charge and discharge conditions, the cycle life typically reaches 500-800 cycles (capacity retention ≥80%).
High-voltage version: To improve the voltage platform, the cathode material undergoes special modifications, but the material structure is more prone to aging under high-voltage conditions. Therefore, its cycle life is usually slightly lower than that of the low-voltage version, generally between 400-600 cycles (capacity retention ≥80%).
Mobile Devices
Ideal for smartphones, tablets, and wearable devices like smartwatches and fitness trackers, offering high energy density in compact sizes for extended usage.
Unmanned Aerial Vehicles (UAVs/Drones)
Perfect for drones requiring lightweight, high-energy-density batteries to support extended flight durations and mission capabilities.
Electric Vehicles
Suitable for smaller EVs including electric scooters and bikes, benefiting from their lightweight construction and high energy output.
