BAK battery capacity is 25 Ah.
The Chinese company BAK presented new batteries of the 4680 standard at a local battery exhibition. The same ones were presented by Tesla in the fall. The Americans are still developing the technology for mass production of their batteries, and the Chinese intend to start serial production as early as next year, writes Itdcw.com.
4680 is actually an indication of the size of a cylindrical battery, where the first two digits indicate the diameter and the second two indicate the length in millimeters. What kind of “chemistry” is used in the BAK batteries is not reported.
The capacity of one battery is 25 ampere-hours at a standard voltage of approximately 3.6 volts for lithium-ion batteries. For comparison, compact “finger” batteries of 18650 size (similar to those used in Tesla Model S and Model X) produced by the same BAK hold 3 ampere-hours. By the way, the last zero in their name does not mean a length of 650 millimeters (it is only 65 mm), but simply a cylindrical shape.
Another feature of the new BAK batteries is their resistance to self-heating. This is important for fast charging with high current. Thus, the Chinese claim that the battery of an electric vehicle with their batteries can be charged up to 80% in about 15 minutes.
BAK already has experience in creating relatively large cylindrical batteries. For example, the company is already producing batteries in sizes 32105 and 32140.