how to check battery life

[burnham2k19egolf]

So lets say I want to check the battery percent I still have on my 2019 VW E-Golf. Is this a good test? So I set in e-manager to charge to 70%. So I let it charge to 70% and of course it stops charging. Then I change the setting to 80% in e-manager. Looking at my charger it tells me how much kWh it has charged. So lets say from 70% to 80% it charges at exactly 3.4 kW of course that times 10 is 34 kW. So then divide 34 by 38 and that equals .89 so is it true that means I have 89% battery life? Tryin to figure out battery life without apps as I do not have.

 

[f1geek]

So lets say I want to check the battery percent I still have on my 2019 VW E-Golf. Is this a good test? So I set in e-manager to charge to 70%. So I let it charge to 70% and of course it stops charging. Then I change the setting to 80% in e-manager. Looking at my charger it tells me how much kWh it has charged. So lets say from 70% to 80% it charges at exactly 3.4 kW of course that times 10 is 34 kW. So then divide 34 by 38 and that equals .89 so is it true that means I have 89% battery life? Tryin to figure out battery life without apps as I do not have.

No not a good way. FYI the theoretical usable capacity is 31.5 kWh when new.

There are charging losses so unless you know the charging efficiency very precisely, that data is useless.

What you care about is battery usable capacity. The only way to find it out in the real world is to charge the car to 100% in moderate temperatures (say 60-70F) and then take the car on a long drive at moderate speeds (around 50-60 mph) until you around 10% (or less if you like) charge left. Be sure to reset the trip meter before you leave on your drive. When you are done, look at the trip meter to see how many miles you drive, the efficiency of the trip, and then calculate usable capacity based on the percentage of the pack you used for the trip. Best of luck.

 

[curtis taing]

It seems like a good, methodical approach to calculating the usable capacity of the battery f1geek. It would be better if I tried this approach and checked. Thanks for sharing.
Wish me good luck.