I'm wrapping up the design for my 48V battery system and I've noticed that many DIY setups use M8 connectors between the battery box and inverter or other battery packs. I'm curious if it's better to crimp ring terminal connectors onto cables myself or if I should invest in pre-made cables, like the ones linked. I don't really see the point in having quick connectors since the battery isn't something I plan to unplug often, but I was taken aback by how expensive the finished cables are. I'm leaning towards just cutting and crimping connectors myself. What do you all think?
2 Answers
I've been using the right lugs that fit my wire and bolts, which in my case is a 2/0 stranded wire and 5/16 bolts. I use a 4 lb hammer with a crimper made for 2/0 wire. I hit it once, twist the wire/lug 90 degrees, and hit it again. Always stick to copper or tinned copper lugs. I've never had an issue with this setup, even at 175 amps from my 48V batteries—none of my connectors have ever gotten hot. Sure, a hydraulic crimper would be great, but if it's not broken, why fix it? Just make sure you remember to put the heat shrink and silicone cover on before crimping!
I just go with the original cables that come with quick connects to M8. Honestly, I’d rather not risk burning down my house just to save a few bucks on cables. Plus, since I'm charging and discharging between 100-400A, there's no room for loose connections. I mean, I can crimp cables at work, but with my hourly rate, paying a bit more for pre-made cables is worth it. Also, quick connects are fantastic if you're looking to expand your setup. You can add 10 more batteries in under 15 minutes!
I totally get that. We use a thermal camera to check our connections under load, but saving a buck isn't worth a potential fire hazard. Plus, if you have access to professional tools, you might as well use them for custom lengths!
That's a solid point! Do you have a specific product link you could share? I'm also hitting around 200A, so I want to avoid any bad connections. Would be great to see what you recommend from personal experience.