The price of LiPo cells available in the US marketplace is absurd. I suspect its mostly due to the difficulty in importing cells in volume from China because of the restrictions in shipping more than a small number of cells. We now stock three commonly used sizes with connectors and safety circuits installed. The capacity of the cells are 400mAh, 1000mAh and 2000mAh and they can be ordered from the store. Orders for 1 or 2 cells ship normally. More than 2 cells require ground shipping because of the restrictions on shipping cells through the mail.

The capacities quoted are measured capacities and not stated capacities by the manufacturer. The capacities are measured using the charging circuit on the boards that we cell and is typically 20% lower than the manufacturers’ stated capacity.

The capacity of a LiPo cell depends on the exact cutoff voltage for charging and discharging. The discharge cutoff voltage has a small effect on the cell capacity but the charge profile and charge cutoff voltage can have a large effect on the total cell capacity. I measure the cell capacity by charging the cell plugged into an ESP32-Bat circuit and once it is fully charged I discharge the cell with a constant current using an electronic load. I set the cutoff voltage at a point where the 3.3V LDOs enter dropout.