Battery charging

[Novice]

I realise this question has probably been answered to its limit, and the patience forum people have I find amazing, so as a novice my question is: my 36v 10.4ah battery only ever charges to 41.7 I realise is not far off but naively assumed it would go to 42, if my question sounds ridiculous my apologies many thanks.

 

[rich c]

Are you measuring it with a multimeter or is that from a display? Check it with a multimeter for accuracy.

 

[Novice]

Thanks for replying, I am using a multi meter.

 

[Lightning P38]

I realise this question has probably been answered to its limit, and the patience forum people have I find amazing, so as a novice my question is: my 36v 10.4ah battery only ever charges to 41.7 I realise is not far off but naively assumed it would go to 42, if my question sounds ridiculous my apologies many thanks.

How much has your battery been used?
Does your charger have a light to signal when the battery is fully charged?
Have you charged the battery overnight?
I would suspect the charger more than the battery.

My 36 volt battery charges to 42 volts. I have about 500 miles on it.

 

[Novice]

Battery charger does have a green light when charged, have done just over 800 miles.

 

[Lightning P38]

Battery charger does have a green light when charged, have done just over 800 miles.

I should add, that my volt meter does not go to the tenths, so if my battery is at 41.7 volts, it would round to 42 volts. You must have an expensive volt meter!

 

[Novice]

Thank you so I am ok then with 41.7? Take care

 

[6zfshdb]

Thank you so I am ok then with 41.7? Take care

I wouldn't be concerned about a .3 volt difference. Unless you have a high quality meter like a Fluke or Simpson, .3 volts is within the margin of accuracy for many cheaper meters.

 

[Novice]

Brilliant much appreciated

 

[Sierratim]

I wouldn't be concerned about a .3 volt difference. Unless you have a high quality meter like a Fluke or Simpson, .3 volts is within the margin of accuracy for many cheaper meters.

Agreed, not to mention the variability in the settings in the various BMS that each battery pack is equipped with.

 

[harryS]

Put your meter on the charger output too, and see what that tells you. That limits your charge, I've got four or five 36V charger bricks. I ended up labeling them, 41.7 to 41.9V per my cheap Craftsman meter.

Most of my batteries drop a few tenths of a volt an hour after being charged. I only had one, a custom pack where the builder put in quality cells that actually held 42.0V for a few days.

 

[Novice]

Many thanks for all your replies it all helps me