Using Lithium Ion batteries - keeping them safe

by Peter
(Sebastopol, CA)

There are many reasons to use a battery management system when installing a Lithium battery pack in an electric vehicle.

A BMS will keep the individual cells at the same state of charge, meaning they will charge and discharge at approximately the same rate. This is important in maintaining the maximum life of the battery pack. It is also important because if a lithium cell is over charged or over dis-charged there is a possibility of fire.

So how do you install a BMS with confidence.

We tried several brands and finally choose Elithion BMS for our standard BMS offering.

Elithion has a mature product that can be configured to your specifications. For example we like to charge individual cells to 3.5 volts and limit discharge to 2.8 volts. Specifications indicate you can charge to higher voltage and discharge to lower, but the increase in capacity between 3.5 volts and 3.8 volts amounts to less then 1% of the cells capacity, but by limiting the maximum charge to less then the maximum allowed we improve the life of the cell substantially.