Periods of non-use that exceed 3 weeks can cause a battery to go into “hibernation”. To get out of battery hibernation you need to charge and then use the battery for a few cycles. During this time you’ll experience a lower range and a bit less power. The battery should return to full performance once you do this a few times.
If you look after it, you shouldn’t need to replace your battery for 4-6 years. Here is how to care for the e-bike battery to maximize its performance and reliability.
The ebike battery uses Lithium Ion chemistry in the form of 18650 cells which look like oversized AA batteries. (each cell is 18mm in diameter and 65mm long, hence the name.) Many of these cells are assembled into a battery to produce 36 or 48 volts and a specific capacity, depending on the bicycle it is made for. The overall shape and physical dimensions of the battery dictate how it is assembled and often also how much capacity it can hold.
https://evelo.com/blogs/learn/get-the-most-from-your-ebike-battery
