I'm currently trying to build a battery charging circuit and decided to reverse engineer the battery management circuit of BeagleBone Blue to understand how it works. Some of my questions are pretty basic/shallow, so please bear with me.
1) The circuit is using a MP2615 for charging 2S Lipo/Li-ion batteries.
As I go through the datasheet, I wonder what happens if you try to charge a over-discharged (unhealthy) lipo/li-ion battery (lets say 1V per cell).
1.1.Q) Will MP2615 still try to charge it in trickle charge mode even the cells are at 1V (I couldn't find anything related in the datasheet with the minimum necessary battery voltage to start charging)?
1.2.Q) It says that Recharge Threshold at Vbatt is 3.0-4.0 V/Cell. Does this mean that it will not charge the batteries at 4.00-4.20 V/Cell? So you cannot charge a slightly discharged battery unless it is below 4.00 V?
2) The circuit has a S8261 for extra protection.
And the model they are using is S-8261AAJMD-G2JT2x which has an overdischarge voltage protection at 2.50 V/Cell.
2.1.Q) As I know that a healthy cutoff voltage for a Li-ion/Lipo is around 3.00-3.30V. So it is not a wise idea to use the batteries until the protection kicks in (2.5 V/Cell)? Why is undervoltage limit so low in BeagleBone Blue board?