Max capacity of 26650 lithium ion battery
Before start, let me explain a general concept of lithium battery’s capacity. The capacity of lithium battery is determined by its structure and material system, that is to say, even if lithium batteries have same structure, but if their material systems are different, then their capacity will be different. The capacity of a lithium battery is affected not only by the characteristics of the material itself, but also by the design and manufacturing conditions of the cell.
Different materials have different charge capabilities, depending on the material’s process ability and compaction density. Based on current situation, the stronger the ability of battery raw material research and development is, the higher the automatic production degree is, and the better the material’s capacitance and processing characteristics are, then the better the material’s electricity is.
For lithium battery, the more reasonable the structure design and formula is, and the higher the automatic production level is, the higher the lithium capacity will be. So what’s the maximum capacity the 26650 lithium battery could achieve? Let’s discuss based on two popular material systems in domestic market.
Lifepo4 (Lithium Iron Phosphate)
3.2V 2500mAh, this cell is designed for big current discharge. It supports 30C constant discharge and 50C peak discharge, the first choice for starting power products.
3.2V 3500mah, this is the highest capacity of 26650 LiFePO4 cells availabe in the market (by December 31, 2016). According to PLB’s product roadmap, it is expected to launch 3800mAh LiFePO4 cell of 26650 in the second half year of 2017
NMC (Nickel Manganese Cobalt)
3.7V 5000mAh, this model has been quite mature, with excellent consistency and safety performance, and cycle life over 1500 times with capacity retention rate over 80%. It is one of the best 26650 NMC lithium ion cells in the market, which has passed the compulsory test of electric vehicle batteries in China. It claims absolute leading position in China, even surpasses Japanese and South Korean lithium batteries in terms of cycle life performance.
3.7V 5500mAh, this cell is an upgrade version of 5000mAh, capacity and other characteristics better than other cells in domestic market.