HV capacity after 10 years/121,000 miles?

There is no one answer because the operational characteristics change so much and it is 'difficult' to measure:

• "Heat is the Enemy"
  • park in shade or out of direct sunlight
  • keep speeds modest, 65 mph top, so the traction battery is not run down
  • regular operation, 3-5 times per week vs once every month or so

Now there is a technique for measuring the Ahr capacity but it requires instrumentation. If you want to measure your traction battery capacity, let me know and we'll go over the technique . . . later.

Bob Wilson

 

Ok, I'm home and we've had dinner. The protocol:

1. Use a data-recording OBD scanner
   • records SOC
   • records traction battery amps
2. Put blocks so car can not move.
3. Force-charge to 80% (note: this heats the battery so do it after an overnight, cold-soak).
4. Begin recording SOC and traction battery current.
5. Shift into "N" - prevents the engine from charging the traction battery.
6. Turn on all lights and accessories.
7. Wait until SOC reaches ~50% and save data.
8. Shift into "P" and let car run until engine stops.
9. Turn off car and let it cool down.

Using the amps per hour over the interval and change of SOC, calculate the Ahr/% SOC. Multiply times 100 and you have a good, first approximation of the Ahr capacity of the traction battery.

Bob Wilson