I always preferred the diy way of things, my question is clear. Is a good enough quality achievable without a professional doing it for me? Also I would really appreciate if you guys could share some tips/pics/info on how to actually do it. We are talking about a 12s10p (or 9p since it’s easier to separate the p groups) from 30q cells for a eMTB build - so the pack would be fitted inside a waterproof case on top of the deck.
I’m looking for any advice from nickel strips to bridging series, anything.
How much time do you have on your hands? Will you be building more packs in the future? If not, then get a pro to do it for you, because spot welders are expensive. If yes, then read through The battery builders club to learn everything there is to know about building safe packs + all the tips and tricks to do so.
Personally, even though I know all the safe building guidelines and have the tools to do so, whenever I can, I get someone else to build the battery for me, because it just takes so long unless you do it regularly
To add to what rusins said, for such a large pack on first go it can take up to 3 full days + you have to order not only spot welder, but nickel, fishpaper, wires connector, hot glue, BMS etc. If you don’t plan to make any more boards or pack, custom made packs are way better and cheaper option.
Quality is subjective.
This community’s battery build standards is high… just a bit too high imo.
First define your own quality standards. Determine if you can build a pack that meets that standards.
All quality-related factors considered, might as well weigh-in the ability to service/repair and the experience gain from building it yourself.
If you decide to go the DIY route, be prepared for
A) at least 3 months of reading the battery builders thread (it’s a monster), taking notes, asking questions etc…
B) making a number of up-front investments that more than negate any savings
C) Running every step of your first battery by the more experienced builders in that thread
Also, if you aren’t acquainted with soldering I’d just have someone build it for you. The only scenario in which building your own packs makes sense is if you plan on building several PEVs yourself. If this is a one-off it just makes much more sense to hire a profesh.
Some batches of 30Q seem to have some cells with self-discharge issues. @pjotr47 knows more about this. But there is probably already a thread about it out there, I’ll try to not hijack this one.
I honestly dont agree with the idea that buying a custom pack is cheaper or that the up front investments for DIY outweigh the cost of hiring someone. I found that despite the cost of a spot welder and other materials it still ends up being a fair bit less for me to build my own pack rather than hire someone. Time and labor is expensive, and for good reason, these packs take forever to build and people who do it professionally charge quite a bit for labor
My first 12s4p would’ve cost roughly 600 dollars from a builder. Materials for the pack were roughly 300-350, and my welder setup was another 350. It did cost more, but yeah not significantly more.
The only real value there is the learning experience which might outweigh the risk in some sense.
But if you are not planning on building multiple batteries, or getting into spotwelders. It’s probably not worth the time/frustration + money to get all the stuff you need. On which you will probably cheap out on. This will make the whole proces a lot harder, especially for someone inexperienced.
Experiences builders know exactly just which heatshrink, hotglue, nickel… To use, usually through trial and error. This is priceless knowledge.
You can disagree if you like but the amout of labour you will put into the pack has to be counted as a cost in addition to the materials/tools cost. And then you also have to factor in the time it takes to source the right materials, shipping and duty costs. You’ll also end up purchasing more wire etc… then you’ll need as well as fish paper, polymide and fibre tape etc… You’ll buy the wrong materials often due to inexperience (fucking shrink wrap! Lol). It all adds up. That being said, once you build that first pack successfully, every battery after that is a lot more economical.
I stand by my original statement. If you plan on building 2 or more batteries and have the time, patience and aptitude to build a battery then get after it. Otherwise, just buy a pack here. It’ll make your life a lot easier and get you safely on the road much sooner.
