Battery quality check
 

I am looking for a 2013 Hybrid to replace my 185,000 '09 Yukon Hybrid. A dealer told me a 72 k mile one for sale in NY had a new battery in 2016 and the battery is at 60% life. What does that mean and how would he know it if it is a fact? How can I check or have checked battery quality when buying a used Hybrid?

Love my '09, 19.5 mpg over the last 20,000 miles, mixed driving and everything still works other than just got a voltage variation code. Still runs on electric, autostops, no other symptoms.

Re: Battery quality check
 

It means he's trying to sell you something. I wouldn't trust that it has any other meaning at all, though I'm impressed he didn't say 90%.

To my knowledge, this value is not tracked by the car. At least it's not on any Toyota or Lexus vehicle, and Toyota makes the battery.

With proper current and SoC monitoring (assume GM Tech2 or equivalent tool), one could discharge the battery over a certain range and use the current/time/SoC change values to extrapolate the pack health.

For example:

A/C or defroster + rear defroster + headlights + parking brake on + in reverse with foot off brake (car held with parking brake) might pull about 8A.

You monitor current and SoC and note that it drops from 60 to 40% SoC in 5 minutes.

8A for 5 minutes is 8 * 5/60 = 0.667Ah

Since you lost 20% in that period of time, the capacity of the battery is 100%/20% = 5 X the measured discharge capacity = 5 * .667 = 3.333Ah

3.333Ah / 6.500 Ah (rated) = 51.3% health.

This CAN be done, but I have never met a dealership that knows what they're doing.

Re: Battery quality check
 

you can just benchmark it by seeing how far that baby goes on EV mode. for every 0.1 miles = 5% of capacity, so if you go 2 miles it's 100% capacity
@25mph
I suggest using a GPS to track the miles rather then the DIC
for better accuracy make sure the battery is warmed up and fully charged by the ECM