HV Battery Fitness

The HV Battery Fitness sheet gives an overview of the battery block behavior

For every battery block, the following parameters are reported:

Avg Bias: every block value is compared to the max value of the whole battery. The difference of the block value from the max value is called Bias. This is the average bias over all the trip. This should be as little as possible. High bias may be a clue of a faulty block

Max Bias: maximum observed bias in the whole trip. A high value suggest the block is fluctuating more that the others

Highest Voltage: highest voltage the block has reached. At least one faulty block has been observed having both the highest and the lowest value of the whole battery

Lowest Voltage: lowest voltage the block has reached. Deteriotated blocks may have lower voltage than the others

Std Dev: standard deviation from average value: Blocks that fluctuate more have higher deviation. This is another sign of anomalous behavior.

Avg Local Delta: each block value is compared to its neighbours

Max Bias @stress: this bias is measured only when the battery is used with high current values. This should give a measure of how well the block behave under load.

Max Resistance: maximum measured resistance. Degraded cells may have higher resistance.

%Time @MinV: Time in the whole trip, the block was the one with the minimum voltage. This parameter filtered on delta above 0.2V, as lower values are considered not significant.

Max Est. R: maximum estimated resistance

Avg Est. R: average estimated resistance

Red and green highlight best and worst blocks for every measure.
Orange values are within 10% of the worst value.

Other measures are related to the whole battery:

Long sequences of delta values above various thresholds are primary suspects of impending battery faults, as explained in this article: http://artsautomotive.com/publications/7-hybrid/140-predictive-battery-failure-analysis-for-the-prius-hybrid/

Required PIDs:

HSD3:
"Batt Pack Current Val"
"Battery Block Voltage -V01"
"Battery Block Voltage -V02"
"Battery Block Voltage -V03"
"Battery Block Voltage -V04"
"Battery Block Voltage -V05"
"Battery Block Voltage -V06"
"Battery Block Voltage -V07"
"Battery Block Voltage -V08"
"Battery Block Voltage -V09"
"Battery Block Voltage -V10"
"Battery Block Voltage -V11"
"Battery Block Voltage -V12"
"Battery Block Voltage -V13"
"Battery Block Voltage -V14"

"Internal Resistance R01"
"Internal Resistance R02"
"Internal Resistance R03"
"Internal Resistance R04"
"Internal Resistance R05"
"Internal Resistance R06"
"Internal Resistance R07"
"Internal Resistance R08"
"Internal Resistance R09"
"Internal Resistance R10"
"Internal Resistance R11"
"Internal Resistance R12"
"Internal Resistance R13"
"Internal Resistance R14"

"Temp of Batt TB1"
"Temp of Batt TB2"
"Temp of Batt TB3"

HSD2:

"HV Battery Current"

"HV Battery Block-01 Voltage"
"HV Battery Block-02 Voltage"
"HV Battery Block-03 Voltage"
"HV Battery Block-04 Voltage"
"HV Battery Block-05 Voltage"
"HV Battery Block-06 Voltage"
"HV Battery Block-07 Voltage"
"HV Battery Block-08 Voltage"
"HV Battery Block-09 Voltage"
"HV Battery Block-10 Voltage"
"HV Battery Block-11 Voltage"
"HV Battery Block-12 Voltage"
"HV Battery Block-13 Voltage"
"HV Battery Block-14 Voltage"

"Internal Resistance R01"
"Internal Resistance R02"
"Internal Resistance R03"
"Internal Resistance R04"
"Internal Resistance R05"
"Internal Resistance R06"
"Internal Resistance R07"
"Internal Resistance R08"
"Internal Resistance R09"
"Internal Resistance R10"
"Internal Resistance R11"
"Internal Resistance R12"
"Internal Resistance R13"
"Internal Resistance R14"

"HV Battery Temp 1"
"HV Battery Temp 2"
"HV Battery Temp 3"

While not strictly necessary, additional PIDs like Speed and SOC, may give a better overview of what's going on, as in this investigation.