Just in case charger does not shut off?

[JohnnieB]

Originally Posted by cgtech

The "max voltage" is a bit higher than the typical voltages seen tho. I typically see 44-46v for 36v packs, and 60-64v for 48v packs. It really depends on the charger's profile.

The max on-charge voltage of 2.79VPC is the highest I've seen published and it is published by Trojan, whose 100% SoC voltage is the lowest (and most common), so it is most likely also a safe max for other brands with a higher 100% SoC voltage.

You are absolutely correct that the max voltages typically seen are lower and that they depend on the make/model of the charger being used.

[bdsii]

Thanks !

[sprivitor]

JohnnieB - I have a PowerWise 28115G04 36V charger. I too have new batteries that I'm charging. I checked the voltage from the first positive and last negative lead and getting about 41 volts. When should the charger shut itself down? I ask because I had one battery get extremely hot to the touch. I replaced it, but I'm apprehensive about leaving it on charge too long. I'm wondering if my charger is not shutting down when the batteries reach their charge. How many volts should I let the batteries charge too?

[JohnnieB]

Originally Posted by sprivitor

JohnnieB - I have a PowerWise 28115G04 36V charger. I too have new batteries that I'm charging. I checked the voltage from the first positive and last negative lead and getting about 41 volts. When should the charger shut itself down? I ask because I had one battery get extremely hot to the touch. I replaced it, but I'm apprehensive about leaving it on charge too long. I'm wondering if my charger is not shutting down when the batteries reach their charge. How many volts should I let the batteries charge too?

A PowerWise 28115G04 typically shuts off in the 44V to 46V range and at 41V it should be pumping out about half of its max amp rate.

Since the six batteries are connected in series, having one battery getting hotter than the other five upsets the apple-cart, but the charge only looks at the voltage of the entire battery pack and doesn't know something is amiss and will keep on charging until the pack's on-charge voltage reaches roughly 45V.

Basically, the charger is behaving normally, it was the battery pack that was abnormal.

Measure the individual battery voltages while on charge. Each battery should have very close to 1/6 the on-charge voltage that the entire battery pack has at the time.

If the six batteries in the pack are fairly well matched, your make/model charge will shut off when each has about 7.5V on them.

[teecro]

And according to Trojan a 36 volt pack may receive voltage as high as 48.6 during the Finish or Equalize phase of the charging sequence.

[Clemsoncartguy]

Originally Posted by JohnnieB

http://www.cartsunlimited.net/battery-break-in-.html

I think I found that link sometime after I posted that question.

I been around deep cycle batteries for years and never realized this . But in my boat it's not as big a deal to me as a cart. I am not a huge fisherman and am usually ready to go before the batteries ran low. And still got good life of of the deep cycles. Course those were 12s and not 6v so I am not sure if any differences between the two

[JohnnieB]

Originally Posted by Clemsoncartguy

I think I found that link sometime after I posted that question.

I been around deep cycle batteries for years and never realized this . But in my boat it's not as big a deal to me as a cart. I am not a huge fisherman and am usually ready to go before the batteries ran low. And still got good life of of the deep cycles. Course those were 12s and not 6v so I am not sure if any differences between the two

All lead-acid batteries are made up from a number of 2V cells and with other factors being the same, the physical size of the 2V cell determines how many AH it can store.

If the six 2V cells needed for a 12V battery and the three 2V cells needed for a 6V battery are packaged in the same sized box, the cells used for the 12V battery will have to be half the physical size of the cells used for the 6V battery since there are twice as many of them that have to fit is the same physical space, so the AH capacity of the 12V battery will be less than the AH capacity of a 6V battery, but other than that, there isn't much electrical difference between 6V, 8V and 12V batteries. The break-in process and subsequent maintenance are the same, no matter how many 2V cells are packed in one box.