Help: 72v 20s7p battery design and/or configuration

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Grider   100 mW

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Help: 72v 20s7p battery design and/or configuration

Post by Grider » Feb 18 2019 5:01pm

Here's the template I'm working with. I'm trying to find the best configuration to divide all 140 cells into 20 in series and 7 in parallel. If anyone likes doing this kind of stuff, chime on in! :thumb: :bolt: :lowbatt: :bolt: :D

Image

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MJSfoto1956   100 W

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Re: Help: 72v 20s7p battery design and/or configuration

Post by MJSfoto1956 » Feb 18 2019 7:20pm

here is just one possible layout of the 7P strings:
triangle battery layout.jpg
Last edited by MJSfoto1956 on Feb 18 2019 8:59pm, edited 1 time in total.

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MJSfoto1956   100 W

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Re: Help: 72v 20s7p battery design and/or configuration

Post by MJSfoto1956 » Feb 18 2019 8:59pm

and in case you are wondering how to wire the serial bits, here is one way to do that:
triangle battery layout.2.jpg

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MJSfoto1956   100 W

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Re: Help: 72v 20s7p battery design and/or configuration

Post by MJSfoto1956 » Feb 19 2019 7:18pm

Here's yet another layout:
triangle battery layout.3.jpg

BotoXbz   1 W

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Re: Help: 72v 20s7p battery design and/or configuration

Post by BotoXbz » Feb 20 2019 6:01am

What kind of current is this pack made for?
You have some series connections where only one cell has the series connection to the next group.
If your pack was welded with normal nickel strip that'd limit your current to 6-7A or heat up and kill those cells.

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MJSfoto1956   100 W

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Re: Help: 72v 20s7p battery design and/or configuration

Post by MJSfoto1956 » Feb 20 2019 8:22am

BotoXbz wrote:
Feb 20 2019 6:01am
What kind of current is this pack made for?
You have some series connections where only one cell has the series connection to the next group.
If your pack was welded with normal nickel strip that'd limit your current to 6-7A or heat up and kill those cells.
Who said anything about nickel strip for serial connections? :P

M

P.S. there are many threads here on ES that show how creative folks have been with regards to wiring their triangle packs.

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