Hi,
The issue we are facing is that the Battery is not charging even we are applying voltage to its terminals. Its also not even discharging when we tried to connect a resistive load to it.
The battery we are using is based on TI chip bq20z45-R1. In our smart battery charger, the MCU (TI MSP430F5419A) charger chip (LTC4100) and the battery (based on bq20z45-R1) are connected through SMbus communication.
Details of the issue:
On giving terminal voltage to the battery we are able to do SMbus communication to battery and were able to read all registers from it. The battery status bits are not showing any errors, but battery is not charging! Attaching here the xls which has the data from the Battery and the LTC chip.
Issue background:
In initial tests status battery was taking a lower charging current 480ma, even though we configure LTC chip for 1600mA. When we analyzed the SMBus activity between LTC and battery using oscilloscope, observed that the after receiving a broadcast from battery LTC the gives charging current of 480mA.
The SBC specification says broadcast of charging current and voltage should be disabled for Level 3 charger by writing to battery mode register. But as per our customer spec we should not change battery params, so we did a test by setting 1600mA to LTC (by writing to LTC chip, NO writes to battery)in a periodicity of 2 seconds. There we got result that the battery started taking charging current of 1600ma, but for some short durations LTC was supplying again lower current of 480ma.
Our doubt was that this is due to the broad cast from battery. So for test purpose we tried disabling broad cast as mentioned in the spec. With this condition the battery was accepting a charge of 1600mA for some time. We were able to charge the batteries from 35% SOC to 85% SOC for one battery and 60% SOC to 70% SOC in another. But then after some time we got the behavior of battery not taking any charging current.
Kindly help regarding this.
