Ok will do! Thanks. Also “pull test” resulted in soldering mostly.
Let me see if I can find some stuff for u…
Pull test just refers to what you did: test weld, remove nickel strip, confirm that it actually welded enough that you leave behind little bits or on thinner nickel tear off chunks and it is sufficiently secured.
On the positive side with the pics you posted it looks solid, it is leaving behind little chunks of the .2 nickel you’re using and even deforming the negative of the p42a to remove it.
My only critique would be the weld placement on the negative and a few of the negative ones look a bit weaker than the positive ones you show. There are a few that look like they didn’t leave behind any material which means that the weld didn’t take.
As far as placement: On the negative side do what you can to avoid welding in the direct center as there are damageable components under that location and it is more sensitive to heat from the welding as well as a higher risk of just outright killing the cell. A small risk but one that’s easily avoided by just spreading the welds closer to the edge of the negative. I try to shoot for the outer third but im not perfect and my probes seem to slide at just the wrong moment 
How are these looking? Hopefully ok, I ran through on my test batteries and now I’m on to real ones for my build. Will obviously order more if need be. Just want to be safe. Thanks
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I tested at these settings for a while and had pretty consistent results. Idk if they are good, but from my research they seemed fine.
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They look fine but try to stay away from the middle of the neg terminals. There’s an internal spot weld there and you can potentially damage the cell.
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yeah I did my best to try and stay away from the center, I found my self wishing that the pre cut nickel strips were just a little bigger
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If I do 2 - 10gauge wires from pack to pack is that enough for 18s6p?
Do you mean from p-group to group?
If so, then 2 x 10 awg is way overkill. Is this a streetboard or a mountainboard?
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street. Ive seen people do 3 x 10awg before, So i was just making sure I didnt need todo all tho. 2 I figured 2 was good.
For a street build, a single 12awg is sufficient for the main terminals. Accordingly, 2 x 14 awg (or 3 x 16awg etc…) would be plenty of current capacity for the series connections.
If you really wanted some headroom, terminate your main terminals with 10 awg and then use 2 x 12 awg or 3 x 14 awg (etc…) for your series connections. This is overkill but will let u drop this battery into a more powerful build thereby future proofing it.
Make sure you’re using high-strand count silicone wire.
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This might be a stupid question. 
Is it a good idea to buy some cells now and use them in a year or later. I guess my question is, how long can you store cells at storage charge before you some see negative effects. The prices will almost definitely go up and I do have some disposable income at the moment, and I know I’ll wan’t to build a bigger pack in the future. Talking specifically about the Molicel P42A.
I have only anecdotal evidence, and this is just from 1 build. I got some nice p42a cells and had to let them sit for a year while I got busy with life. They tested at 3900 and 4000 capacity because they were exposed to low but not dangerously low temperatures sitting in my garage waiting (my guess)
I think if you store them well they will be fine. Don’t be like me
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I just recently finished some testing for my Patreon supporters of some P42A’s that had been in storage, unused, for 8 months to 4-1/2 years.
IMO you shouldn’t have any issues with 2022 or 2023-dated cells stored at room temp for a year.
In general though it’s better to buy cells when you need them and not in advance.
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Thank you. very helpful as always! Is there a logic that its best to store them in a colder place, like a cellar? I’m guessing its around 15-20 deg. C all year round.
Perfect.
Room temp to a little cooler is best as it does slow down aging but doesn’t cool them down enough for condensation to be a problem.
High humidity isn’t good though since they can rust. Best to store them in zip-lock bags (or the equivalent) if the basement is damp.
Just a side note…I don’t recommend refrigerating or freezing cells as that can cause condensation issues and just doesn’t slow down the aging enough to be worth it unless looking for 10 years of storage or something wild like that.
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Thanks for the tip, I have vacuum sealer and tons of silica gel so that would be perfect.
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That’s nothing. My Molicel P26A waited for me to finish my first build since 2021. 
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Nice, got my first best range test today on the “aged”12s8p and we are at 3.5v per cell with 32 miles down range.
Didn’t hit it hard but was only holding back at the end. They seem to recover quite a bit after a 10 min rest. 10/10 would make a bigger one again. I think im a size queen for batteries 
i keep thinking about making top mount vesc box and making it 16s… next build next build. Don’t mess with this one it works lol
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I discharged my 10s3p pack the first time yesterday to 33V did a total of 24 km
Pretty happy with it. My work is 10 km away The skatepark only 2km and the city center only 5km. 
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