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Requirements

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Part	Qty	Image	Notes
Battery Housing	1	Image Added	AliExpress: https://www.aliexpress.com/item/1005005381700651.html?spm=a2g0o.order_list.order_list_main.11.43351802mqQ8Mr

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18650 Litium Ion Batteries	10	Image Added	I had some of these kicking around.  Test at about 2000 mAh each which would make this battery a 4Ah battery.
Spot Welder	1	Image Added	DIY Battery Spot Welder

Specifications

Configuration: 5s2p

Other Battery

Inside a Dewalt Knock-Off Battery 

I had another battery pulled apart to fix the thermistor so here is what it looks like inside.

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Build

Spot welded the batteries and wrapped in kapton tape. 

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Soldered on wires and inserted into battery base.

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Assembled top portion

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Final

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