I think it looks pretty decent, all things considered. Definitely way better than most mass-produced battery packs that make it into eks8. Balance wires look clean.
I’d like to see something a little more robust than foam as a separator between the pack halves. Some plastic from a cheap cutting board or similar would be an easy swap.
If it were me, I’d probably do something about the solder-soaked series connections, even if all I did was take some flush cutters and cut out the middle, and add two pieces of 14awg in its place, without desoldering the rest of the wire.
Thank, for some reassurance. I know the soldering is not on point. I was thinking of redoing the series connections, but it didn’t occur to me I could just snip the hard wires away and solder on some flexible ones. I am a bit afraid of handling the pack. because I seen some videos of those things going up in flames + I newer did any soldering before that.
I will swap the foam for some hard plastic…that is easy enough to do. Thx for the tip!
So you think the balance wires are good enough? No need to cover them with neutral cure silicone or something like that?
I might.
But @Anubis is right, it could take years.
I’m sure a few pre-production samples will be floating around that someone sold off or gave away but otherwise we have to wait for packs to be salvaged from damaged cars or for excess inventory at a customer to be sold off.
Balance wires are fine, just maybe add a layer of kapton over it all.
Since your pack has zero flex tolerance, then you need to strap the battery something flat and stiff than is not the deck itself. This separates the flex of the deck from the battery.
I covered everything with kapton tape. I just forgot to take a picture.
I am actually planing to enclose the battery in this enclosure
Ad a wooden riser between the deck and the enclosure so I can take the whole battery off.
Would that be stiff enough? Any suggestions for a light stiff material?
What gauge Nickle do you use over the top? I did try that, with a Kweld but I didn’t have great success making it a solid connection. Using the TIG welder made amazingly solid connections the only issue is sometimes I lost a battery to blowing out the can on the negative terminal 4 out of 48 did that. The only reason I want to use copper is the current-carrying ability and the heat that is generated by a poor conductor like nickel in the 150A area. Because the connections between the packs are so short voltage drop is less of an issue. I would like to do a load test of some sort and see if the temperatures of the nickel at peaks of 150A that you might experience while esk8ing, I suspect that it might not be that bad even just using 0.2mm, I’ve just not seen anyone test it. I was thinking of testing it with just one p-pack and a heating element as the load.
I have an update, FYI. I’m fairly certain that P-pack 4 has a cell that is stuffed or not connected, it charges faster than all of the others and drains faster than all the others. And P-pack 9 I think is just really low (SOC) compared to the others. I’ve ordered a Lab power supply and a battery capacity tester and I’m going to test the capacity of each P-pack and fully charge each P-pack to 100% SOC individually. I’ve also got an xlite12 BMS arriving soon, that I’m going to use. The LTT BMS balances very strangely, it seems to be in 2 groups only that it can balance and it either balances while charging or while not charging but not both, which means pack 4 gets to cut out voltage and the whole pack stops charging and it won’t balance down pack 4 so it will never start charging again, and the pack never reaches full charge. It sort of makes me wonder what my commercially bought boards are doing with the batteries given you can’t see cell voltages.
There’s a distributor in the US, but I bought mine from Germany and it got here faster than ground shipping within the us would’ve arrived. Then I got my lipos from hobbyking.
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