Stackable power wall kit with 18650 on ebike

General Discussion about electric bicycles.
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cwah   10 GW

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Stackable power wall kit with 18650 on ebike

Post by cwah » Nov 24 2019 6:16am

hello

Anyone used this for their ebike?
https://s.click.aliexpress.com/e/AvtwcITKj

I think it's possible to stack as many as needed but no idea on reliability on ebike with all vibration

john61ct   100 GW

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Re: Stackable power wall kit with 18650 on ebike

Post by john61ct » Nov 24 2019 11:20am

possibilities in that design outer case to clamp physically with padding to absorb shock/vibration

but would want parallel at the bottom level, then treat each group as a single cell.

allowing for flexible xPyS grouping using jumpers maybe

miro13car   1 MW

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Re: Stackable power wall kit with 18650 on ebike

Post by miro13car » Nov 24 2019 4:11pm

imagine
if you add resistance all those contacts ...
vibration even with padding is going to loosen those contacts sooner or later.
Eplus, Bionx

MikeSSS   100 W

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Re: Stackable power wall kit with 18650 on ebike

Post by MikeSSS » Nov 24 2019 11:48pm

That company has 10s 36v, 13s 48v, and 14s 52v battery holders for 18650 cells.

The battery holders can stack up to make 2p, 3p, 4p, etc batteries.

That is a very interesting concept. If a cell goes bad in say a 13s stack, you just replace the one cell, no spot welding.

I did a 15.3 mile ride the other day and averaged 2.7 amps, using my 13s 4p battery, each series group would be providing about 0.7 amps. That should be well within the capabilities of these battery holders. The holders use a 15A fuse and charge is recommended to be limited to 2A when charging the holder as a unit.

There would be no BMS, occasional balancing would be done by individually charging each battery holder unit.

For low power applications this should work, but it might not be cheaper than buying a pre-made ebike battery on ebay or Amazon.

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dogman dan   100 GW

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Re: Stackable power wall kit with 18650 on ebike

Post by dogman dan » Nov 25 2019 7:32am

Hmm, interesting. Little disc of lead in each contact, tightening the spring pressure and improving the resistance?

Maybe solder blob on each spring?

Seems like it could be a great thing for those with a pallet of laptop packs.

MikeSSS   100 W

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Re: Stackable power wall kit with 18650 on ebike

Post by MikeSSS » Nov 26 2019 1:48am

Battery building the easy way.

Model railroaders use a conductive grease on track connections. That might be just the thing.

Some 18650s have a small dome on the positive end, those made for single cell flashlights and stuff. Cells made for spot welding don't have that dome, they might be shorter than the dome cells.

Perhaps the cell holders have enough room and spring travel enough to work with both kinds of cells, hope so.

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MAXIMUM_AMPS   10 mW

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Re: Stackable power wall kit with 18650 on ebike

Post by MAXIMUM_AMPS » Dec 02 2019 5:35pm

cwah wrote:
Nov 24 2019 6:16am
hello

Anyone used this for their ebike?
https://s.click.aliexpress.com/e/AvtwcITKj

I think it's possible to stack as many as needed but no idea on reliability on ebike with all vibration
I've seen those, they're primarily made for powerwalls, and other low-current stuff. Performance is similar to the Vruzend V1.5 kits.

They could work on an ebike for sure, but when you start asking for >5A per cell, you need spot welded connections.

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