What do you mean by range extender pack? Are you planning on changing out the pack on a long ride? Connecting it in parralel with the pack that is in the beard?
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Yep I see no problem with two packs in parallel.
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What cells are in the board pack? This could be dangerous if the cells have vastly different characteristics and internal resistance. They would discharge at different rates
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but they are in parallel so they will quickly balance. I don’t understand why are people so scared to use two packs in parallel. That is common upgrade for m365 scooter for example. Chinese shit battery parallel with stock
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Personally I disagree.
IMO it is unsafe to use differing cells regardless of them being in separate packs or not. The logic in my head is that: the load will not be evenly distributed to the two due to the difference in IR meaning one pack will drain faster than the other, causing the other to drain into the pack with a lower voltage.
My only evidence to back this up, is a friend who bought a new pair of the same lipos for his Trampa, he had 2 in case, 2 strapped to top of case, he wired them in series and parallel so they were 6S2P 12000mAh I think. The first were the originals with mileage on them, maybe 6months. iirc the older ones were hotter than the newer ones when he finished riding. My thinking is the older ones were constantly draining into the newer ones which were discharging faster, but I don;t have any way to substantiate this claim.
The amperage draw on those is probably 20A peak? maybe less. Not 50A-80A we are pulling, not sure it’s a safe reference point.
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Just saying that Australian dude building his own electric car (@?) is using lipos for the power and other cells for the range and plugging in parallel
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What’s a good non conductive tool to use to slice open shrinkwrap on a battery pack?
I have to slide some fishpaper in, but I’m not sure what I should use to get the job done 
Regular knife (metal) don’t cut too deep, and once you got a little sliver started it should pull apart just fine. Like a potato chip bag is strong against tearing, but one little nick and you can open it easily.
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I used to work for Future Motion 
Quite a few things done backwards around there. lol
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I saw a 5 pack of ceramic Dinner knives for 10$ in a hardware store randomly and bought them for this reason.
I had a ceramic exacto knife blade but they were 2-3 times more expensive and chipped way easier
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Is there away you you could tie in the b- lead to a dpst Switch into your board Main power button?
That way the balancer only balances when riding.
If you disconnect b-, does that stop the balancer?
I’ve been really interested in these boards, but my proper RC balance chargers have kept me really happy. I can always see if a p group is being stupid, but my garage does look like I’m doing shady shit to anyone strangers who happen to see me.
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I have a ceramic hobby knife. It is a plastic handle and just the tip is a ceramic blade. Great for working on batteries.
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More like 40mm (±1mm) x 175mm after you’ve added screws, busbars, and eyelet terminals for balance leads.
.25mm pure pure nickel. How much current/ total watts would you guess this can carry? My guess is 9000 watts?
I’m thinking of taking solid wire -10 feet and sound a direct short with a shunt/ meter and using a flir gun to see when it starts cooking.
Any ideas? I know there is math that can answer , but I like the brute Force method.
Might double stack them, or infuse with Cooper sheet. TBD
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When silicone-ing cells together, do yall do both sides? Or is one side enough?
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Your talking how to keep the p groups from shorting?
While I am using two different cells in each parallel pack, one definitely isn’t lipo. Those SPIM08 cells are in fact LiIon, and are very safe cells to use
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I always do both sides. If i’m in a hurry, i let one side cure, flip them, goop them and then wrap them straight away with fishpaper so I can start welding.
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