Ask HN: What are you working on (August 2024)?

Hey guys! We're engineers/designers from France, and we've built the Ultimate DIY Battery that you can repair and refill!

It works with 90% of the bikes/motor brands on the market, so I assumed that some people here might be interested, if they got a non-functional batteries but they still want to use their e-bike?

We believe that everybody should have control about stuff they own, and we should fight against planned obsolescence!

Here are a few videos about our founder on the battery itself, why we built it, and how to assemble it:

- What is the Gouach Battery: https://www.youtube.com/watch?v=NsuW1NPkvNk

- Presentation of the pack: https://www.youtube.com/watch?v=mLoCihE0eIA

- Presentation of the fireproof and waterproof casing: https://www.youtube.com/watch?v=EDJpt7RDbRM

Here are the juicy bits: https://docs.gouach.com

We'd love some feedback from the e-bike DIY builder community

Oh, and it's launching as a Kickstarter in September and there is an offer for early-backers here https://get.gouach.com/1 for a 25% discount on the battery!

You can follow us on Instagram https://www.instagram.com/gouach.batteries to get the latest news!

Would order instantly. I have a bunch of e-scooter 18650 battery packs that would be nice to convert to an e-bike one.

If Kickstarter is starting in Sept, then I guess it will be another 1-2 years.

I thought the reason the packs are sealed is to stop amateurs from swapping in cells of differing voltages, which short each other out and cause sparking/fire hazards. There's a reason li-ion battery charging is current-limited, they have no internal resistance.

from their homepage :

A Fireproof Casing which REALLY Works!

Scared of battery fires? I know that we are!

This is why our Infinite Battery comes with a casing that we designed to resist the heat of a fire, thanks to it's thick aluminum casing, and a design which dissipates heat quickly.

And YES THIS WORKS! We have put a massive effort in making our casing sustain the battery fire, and extensively tested it (videos coming soon), so you can sleep safely (and us too!!). See our complete fireproof testing on our documentation/FAQ

oulipo, gouache.. these are names i haven't heard in a long time

jokes aside, i was curious if weld-less 18650 packs would be possible... seems like you guys answered that 10 years long question :)

kudos

It's a very nice concept and I think it's much better than the held-together-with-duct-tape concepts usually seen in diy bike conversions.

That being said, I am a bit skeptical about your claims to be fireproof. Did you try to start a battery fire inside your enclosure? Aluminum melts at about 600C, while lithium burns much hotter than that.

Could this also be used to create external power stations with 230V plugs ? For example to take in a car / van, and recharge with solar panels

Prevention is better than cure though. plus you've got to consider cell gassing/venting/explosion risk/toxic fumes as well as fire prevention.

If they were doing per-cell protection, fair enough (cheap 18650's don't have cell protection usually), but I think they are still connecting 4 cells in parallel, with only serial-bank MOSFET's like in usual sealed packs.

Super cool! Any plan on making different form factors? For electrified cargo bikes, the battery is better placed bellow the cargo [0] so a squarish and flatter pack would be nicer.

[0] This build for example: https://danielbuettner.medium.com/building-a-custom-e-cargo-...

Dude, this is amazing. It deserves its own HN post!

(if they're using PTC themistors between the parallel cells to prevent over-current, it's all good though I suppose)

this is amaizing...

As I understand it, it's somewhat the opposite for internal resistance. You need to have current limiting in place because the internal resistance of the cell is turning that current into heat, and heat is the enemy of batteries.

(Probably there's also a complicated chemical reason for current limiting that I don't fully grasp)

This is a great idea. I'm actually researching DIY solutions to electrifying my boat (I was a USAF electrician, once upon a time) and the prepackaged battery solutions are so expensive and inflexible. (Granted, for marine use there are some extra considerations...)

>>have a bunch of e-scooter 18650 battery packs

Where get?

There is a guy that rides the trail near me thats riding an ebike with a triangular battery pack that looks identical to one some HNer built here - He's too fast and I havent been able to stop him.

Another question for the DIY e-bik crowd, is what kind of OTS motor could one harvest, like a motor from an electric lawm mower, or edger, weed-wacker? Are there power tools where the electric motor is useable? (like how people originally used mower engines in goKarts and such?

Also, for fireproofing - mix Powdered Aerogel into a Silicon Slurry and dip the battery in that - the silicon and aerogel will make a heat sleeve thats quite fire resistant.

Since you have the ESP32 - can you emulate the Apple Airtag on it please.

I have a $7,000 Orbea E-bike and I have an Airtag hidden in it. Its a great feature.

Not sure if I could redo the Orbead Battery this way because its internal to the frame - but it does have an extended battery pack option - perhaps this could be wired to use that connector as your interface allows for any ebike it seems?

The post recently on HN about the flipper zero being able to emulate the airtag is pretty nifty, and you could use these guys effort:

https://news.ycombinator.com/item?id=41287031

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I LOVE this project.

I want.

Actually, Can I ask that you add a LORA transceiver network in the build since you have the ESP32 (maybe update it to the ESP3250?) :-)

https://www.youtube.com/watch?v=40llxjrIG3w

Imagine being able to lora talk back from your bike to the trailhead, or your campsite.

And do you have a better version of Shimano's E-Tube iOs crapware?

EDIT: Since you have THIS: https://www.youtube.com/watch?v=EQHZFRHiUdg

The Goauche BMS Tesrt Bench needs its own video/HN post - and this is exactly what would be great info to get via a LORA messaging for all the telemetries from the pack?

WOW:

https://www.youtube.com/watch?v=9sEuBDA_xb8

I want to open a Goache Plant in California. Seriously.

I'm the CEO of Tile and we are working on a line of products for theft.

As a genuine question, I'm very surprised that many people don't seem concerned that AirTags alert thieves to their presence. If your bike is stolen the thief will get the notification, even if they are on Android (with the new shared platform rogue tag detection).

I'm trying to understand the user psychology here - not pitch our own products.

Do you have any specific features you would like to prevent theft?

The fact that something is being tracked and the thieves know it’s being tracked is a deterrent itself. Like the value of stolen iPhones crashed because activation lock made them worthless. So they moved on to Samsung Galaxies, until they implemented their own activation lock.

If you steal a bike with a tracker on it you’ll probably leave it right there for the real owner to find.

Howdy!

Great to meet you. I have a ton of thoughts on this matter, but not well threaded for quick reply: so forgive the stream-of-thought nature of the following.

There is no real secret answer to stopping bike thieves, because the primary problem is both cultural and infrastructure.

We dont have bike culture that allows for safe bike leaving-about, and we dont have bike infrastructure for safe bike locking-about. (Bike Hack SF: Take your nice bike into a nice hotel and tip the DoorMan $5 to check your bike into luggage check rather than lock it up)

So, my airtag is in a case with security bolts under the bottle cage - and its more a check that I can know where it was last seen. Though I didnt remove the chirper.

What if you could have a TILE that is the fob for this battery. Where the battery wont go unless the paired Tile Fob is present?

A Lora Tile would be killer If you had a Lora network on this battery, with a TILE app infra on top of it and all the batteries talked to eachother - you built an anti-theft-mesh so all the bikes tiles all tell eachother about themselves.

Tile integration with Shimano Motors and e-tube iso app to stop the motor from running unless Tile fob/phone app present. A magnetic Solonoid crank-shaft-blocker.

And above all else pushing for better bike policies in municipalities.

>and extensively tested it

By themselves or independent 3rd parties with deep experience in battery safety testing?

Of course I know this, but I am trying to go deeper. With AirTags and the new standards you literally can find and disable the tag for anyone using the Google or Apple networks.

I am surprised that people think the benefits of AirTags outweigh the downsides given the alternatives, of which we are one. I'm mainly just trying to learn.

I also think you probably are overestimating the deterrent value. Thieves are not necessarily thoughtful and the alerts aren't real time. Once they get the alert they might ditch the bike, but if it is back at their garage they will probably disable or remove it.

I also am a bit triggered by this line "Honestly, you as the CEO should know this." which is on the edge of being an ad hominem. Why did you choose to include this? And wouldn't you know that I know these things? Like I am asking questions to get nuanced user feedback. Do you think someone who runs a consumer product company (I started Life360, Tile's owner), isn't deeply aware of how customers think?

We are doing a satellite integration with Hubble Network - 24/7 global coverage, no increase in battery life. It sounds like scifi but 2 satellites are up. Give us a year...

First, I want to apologize. The last statement came out a lot more combatant than I realized. So I removed it.

I was a Tile wallet user until I stopped carrying a wallet completely. There are 2 types of thieves: the professional and the opportunistic. Opportunistic, the majority, aren't doing more than they have to and if the bike has a tracker they know about it makes it less appealing. And if you can get the casual thief to give up immediately then the device has already payed for itself.

The professional will chop it immediately. I see kids in my neighborhood with $2000+ Trek Marlins, with all the expensive mountain bike parts removed. They simply wanted a bike to freestyle on. And doing all that probably took hours if not days. The professional is not going to spend anymore time than they have to disable a tracker when there are better options all around.

Hi - Who is 'we' and how can I get involved.

I tried to build this after leaving Lockheed in 2007 where we built the RFID tracking for .mil as Savi Networks..

All the cell integrations (pre IoT) were cost prohibitive.

Its wonderful to see how much has taken place in this area since a bunch of us tried and failed to get funding back then :-)

Also spot welded connections work well, transfer reasonable amounts of current and don't tend to vibrate off during use. We tear down packs at my job and there are warnings inside some not to re-use cells for vapes, they really don't want you taking these apart. Larger packs like EVs and E-bikes are probably worth refurbishing and repairing.

> riding an ebike with a triangular battery pack that looks identical to one some HNer built here

You might be thinking of jacquesm and this bike:

https://jacquesmattheij.com/long-range-ebike/

I want to build things using Instant DB... I keep finding ShinyObjects here, but - Tiles using a LORA Network which updates a csv/json style payload and transfers GPS through lora messages.

https://news.ycombinator.com/item?id=41287031

Can you manage TILEs via Meshtastic? https://meshtastic.org/docs/software/

https://www.youtube.com/watch?v=40llxjrIG3w&t=44s

I think there a lot of interesting things to make bike mesh a part of a security fabric - but ensuring that there is no way to spy on location data thats not yours? Doubt thats possible...

Because loosing something to theft is bad but being stalked is worse.

To do this with any DC battery you add a solar battery charger to accept the panels and an inverter to turn the DC into mains 230V you can use.

> a casing that we designed to resist the heat of a fire, thanks to it's thick aluminum casing, and a design which dissipates heat quickly

Thus turning a difficult to deal with Li-Ion inferno into a slightly less difficult to deal with block of superheated aluminum, that will happily set on fire anything that looks at it funny?

This is always my concern about fire-proof metal casings for batteries: where do you put that so it doesn't set anything on fire?

Im curious how Tile addresses this concern for the safety of individuals themselves in the opposite direction. I know people who have been stalked and assaulted before. Does tile have protections against this for people hiding tiles in your vehicle or bag?

Interesting, thanks for the insights.

My cofounder from Life360, started Hubble Network, with this in mind. Add me on LinkedIn - Chris Hulls - and I'll reply to you there.

yes! Bigger models coming early 2025

This would work perfectly indeed!

Thanks for your message! The battery is already designed and in production, it's running on 1500 free-floating e-bikes in France without issues since around 2 years

We're doing a Kickstarter because we're a startup so we need the upfront money to buy the parts and build the battery! We expect to ship to Kickstarter customers in November 2024!

Indeed, we recommend swapping all the cells at once! But using our battery it means that you recover cells in perfect conditions that you can use in second life applications!

Indeed it will get hot, but it is better than having one's house burn down! :)

Thanks so much for your messages!! Appreciated!

Yes, we totally can add LoRA, we want to do this soon! You can contact us on contact@gouach.com for more infos!

Hey! We'd love to chat to see if we could integrate in our battery! Can you message us at contact@gouach.com ?

Haha! I'm a fan of OuLiPo :)

Yes! the pack is using 18650 cells, and a 21700 version is coming early next year!

Thanks so much!! Appreciated

Thanks so much!! Appreciated! We did one a few weeks ago, we don't want to spam so I'll probably add one when we start the Kickstarter :)

Thanks so much!!

Yes, it works because we're using a thick aluminum casing and a specific design to evacuate heat fast

Videos coming soon!