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BQ34Z100-G1: Understanding power calculation in device

Part Number: BQ34Z100-G1

HI Support team

My customer is asking the following question Can you help answer this :

The z100 data sheet includes the following descriptions of AvailableEnergy and AveragePower:

 

7.3.2.5 AvailableEnergy(): 0x24/0x25

This read-only command pair returns an unsigned integer value of the predicted charge or energy remaining in

the battery. The value is reported in units of mWh.

7.3.2.6 AveragePower(): 0x26/0x27

This read-word command pair returns an unsigned integer value of the average power of the current discharge.

A value of 0 indicates that the battery is not being discharged. The value is reported in units of mW.

 

When I log z100 data, Available Energy is not simply the reported Remaining Capacity in mAh times the reported voltage. It does not appear to be referenced to a single cell either. It is something different. For example this is z100 data taken from a 7S battery. One data set during Charge and one during Discharge::

 

Rem Cap (mAh)             Voltage (mV)    Current (mA)      AvailableEnergy (mWh)            (Voltage/7)*Rem Cap    AveragePower (mW)

8646                             29365               829                   31786                                       36269 (Not 31786)         3478                                   

2980                             24934               -3407                9853                                         10615 (Not 9853)           -12136                          

 

I want to get an understanding of how AvailableEnergy is calculated so I can use it properly in a system.

Many thanks

Jeff