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by gruturo 213 days ago
You should definitely replace all cells together - a new cell will have a different capacity and could "charge" an adjacent older cell to rebalance, causing a fire (but a good BMS won't allow that - on the other hand you'll be limited by your weakest cells despite having put some new ones in)

For me the value proposition would be to avoid what happened with my previous ebike: after 3 years I wanted a new battery as the old one was on its last legs, and it wasn't produced anymore. Or what's happening with my current ebike: to avoid the same story with the battery, I am thinking of buying an extra one now while it's still produced, and it's outrageously expensive (550EUR for roughly 500Wh, which is about 7..10x the price of the cells if you are a careful buyer).

(You can fit a new battery to any bike with (sometimes lots of) extra work, but esp. my previous one had a weird solution where it slid into a rail above the rear wheel and it would have been a PITA to reengineer.)

So yeah if their thing works I'd consider a bike using it, on economical grounds mainly.
1 comments
oulipo2 213 days ago
Exactly! That's precisely why we designed the battery, to let people be in control of their own stuff!

Our batteries have now be running for close to 3 years on shared mobility ebikes, so they are well-tested indeed! If you want more infos, send us an email at contact@gouach.com :)

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gruturo 213 days ago
At 199EUR without the cells, I'm _almost_ tempted to go for it. It's a bit steep but the savings on the cells would already make the whole thing overall viable. If it had the ability to charge from USB-C as a contingency solution, it would be an impulse buy.
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oulipo2 213 days ago
Indeed! We've been asked for the USB-C quite a bit so we might do that in a future version, but it increases the BOM price for our shared mobility fleet customers which are quite price sensitive!

Indeed it's 199 eur, but it's high-quality, certified, comes with a waterproof and fireproof casing, connected, with real-time safety alerts, and when you'll eventually need to change the cells, you'll only pay 50 eur to refill your battery!

Compared to that, an equivalent Bosch battery goes for 500 to 700 eur (for the same quality). We're even compatible with Bosch gen 2/3/4 (non-smart)

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