This is a design I'm working on. The idea behind the wave pattern is so that they can be stacked without losing all too much space compared to rectangular cell packs.
I'm putting a 60C thermal fuse in between each cell pair. Should a cell overheat, the fuse will pop and render the pack useless. This is an additional safety feature on top of a BMS and periodic manual checkups with a thermal camera.
The idea behind all cells pointing upwards (positive facing up) is also a safety feature. Should one start to vent or catch fire the flames will go up immediately triggering an extinguisher above the cell pack.
Let me know what you think! I'm not finished with it yet but if you want the design files already let me know I'll send them to you.
Edited with a deshittified version of imgur.
12 Comments
j4k3@piefed.world · 10 pts · 315d
Would like to see, but imgur is stalkerware bordering on malware. Sorry this comes across as negative digital neighbor friend. If at all possible, use your instance's pic rs host, a federated alternative, or other honest and straightforward host.
I know it is hard to care when doing electronics and all of the stalkerware nonsense in that space. I've got my own bedroom lab.
Rolive@discuss.tchncs.de · 4 pts · 315d
Yeah. I see what you mean. I find it acceptable for certain use cases like a quick showcase for stuff I want to share freely anyway.
It's a bad habit.
Olgratin_Magmatoe@slrpnk.net · 4 pts · 314d
Looks beautiful. What are you planning to power with it?
Rolive@discuss.tchncs.de · 4 pts · 314d
The plan is to have it function as a home battery, connected to either a solar panel or a small balcony wind turbine. I also want to charge it when the electricity cost is low and discharge when the electricity cost is high on average.
Another part of the project is to build a grid-tied inverter.
RustlingLeaves@slrpnk.net · 4 pts · 314d
In case it is blocked in your region: https://imgur.artemislena.eu/a/aQJA9o9
Rolive@discuss.tchncs.de · 3 pts · 314d
Ooh, a deshittified version of imgur? Or did you invent time travel?
RustlingLeaves@slrpnk.net · 4 pts · 314d
Third party frontend.
czardestructo@lemmy.world · 3 pts · 313d
May I ask why 18650? 21700 have better energy density and theyre easier to get these days. The price has also come down a lot.
Rolive@discuss.tchncs.de · 3 pts · 313d
Because I have a metric shitload of them available. Indeed if i was going to order fresh cells 21700 is better especially for a home battery system.
czardestructo@lemmy.world · 4 pts · 313d
Way better to use your old junk. I like that youre make your own home battery, ive considered it. I have solar installed and would love to not consume grid power at night. I'm thinking of installing a bank of lead acid batteries under my ground mount solar that would dump power into my home at night.
ultranaut@lemmy.world · 3 pts · 315d
Looks awesome. How much space is between the batteries? Could you push air through the gaps to cool them?
Rolive@discuss.tchncs.de · 4 pts · 315d
Thanks! There's about 3mm space in between the batteries so air would easily flow through. I'm not sure if that is preferable though, ideally the cells do not get warm at all.