We received some batteries back from our customer, none would charge and no voltage was present on the pack terminals. The packs were opened and the cell voltages were measured at 1.7 to 1.8V in all 3 packs.
On one pack the cells were charged directly until the pack could be read with an EV2400. In the PF Status Register the VSHUT bit was set. No Safety Status bits were set. After the cells were recharged the pack was given a RESET command and an Impedance-Track Enable. We were able to operate the packs as normal after that.
The customer said that their customer left the batteries installed in the product (a small portable computer with Windows Mobile 6) for an extended time (Probably more than a week) and they wouldn't recover after that.
The customer's application includes a built-in smart charger that is powered by the internal bus which gets its power from the battery. Could this have been why the pack thought there was a charger present?
What exactly does the Charger Present voltage signify?
