PDA Li-ion battery can't be charged with direct charger, and it can only be charged up to 2% each time. What is the reason?

One, try with another good battery, if the recovery can be charged, then the original battery aging, sitting charging voltage is slightly higher, can be charged, direct charging is slightly lower, can not be charged.

Second, if another good battery is also the same situation, it can be identified as a cell phone charging circuit problem, the phone has a part of the charging circuit, the use of direct charging of the power supply to the battery charging management, the phone should be the part of the phone is bad!