Series and parallel batteries......?

Batteries, Chargers, and Battery Management Systems.
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Branmoto   1 µW

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Joined: Apr 07 2019 10:13am

Series and parallel batteries......?

Post by Branmoto » Apr 07 2019 10:24am

Might be a common sense question, but I feel like I'm thinking about it too hard.

My goal: 36v 60ah battery.

Can I hookup 3 12v 20ah batteries in series and parallel?

12v 20ah + 12v 20ah + 12v 20ah = 36v 60ah, right?

Thanks!

mark5   100 kW

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Location: USA

Re: Series and parallel batteries......?

Post by mark5 » Apr 07 2019 1:07pm

You'll need 9 12V 20Ah batteries connected in parallel and series to get 36V 60Ah.

Make 3 paralleled groups to get 3 12V 60Ah batteries and then connect those 3 in series.

Or make 3 series groups to get 36V 20Ah each and then connect those 3 in parallel to get 60AH.

Branmoto   1 µW

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Joined: Apr 07 2019 10:13am

Re: Series and parallel batteries......?

Post by Branmoto » Apr 07 2019 2:00pm

Wow, thanks for the reply....I think that might be too many batteries.

I might just stick with 3 12v 20ah batteries and hook them up for 36v 20ah. Limited on space is why.

Hillhater   100 GW

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Location: Sydney ..(Hilly part !) .. Australia/ Down under !

Re: Series and parallel batteries......?

Post by Hillhater » Apr 07 2019 4:10pm

I guess you are talking about Lead acid/SLA batteries ?
That is where Lithium can save you space and weight. :wink:
.....at a cost ! :?
This forum owes its existence to Justin of ebikes.ca

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dogman dan   100 GW

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Location: Las Cruces New Mexico USA

Re: Series and parallel batteries......?

Post by dogman dan » Apr 08 2019 6:51am

Yeah, just the weight of 36v 20 ah of lead is about the max for bikes to carry. Try to rig one on each side of a rack, pannier style, so you only have one up high on the bike, on top. Or maybe one in the triangle of the bike.

If you can afford it, 36v 20 ah of lithium is so light and small, it carries easily on rear racks, or in the triangle of many bikes.

Figure on about double the range from lithium, because lead has so much peukerts effect. If you use lead, stop when its only half empty, or it will die in a few months. You will need new lead every spring even if you are very careful.

Still, lead can work ok if you only need about 10 miles of range. Same size lithium lasts 2-3 years easy, and can go 20 -30 miles easy.

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