Not having a cable tie on the connector offers no charge protection.
This simply prevents the connectors from vibrating apart inside the enclosure.
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This setup is dangerous. If you ever inserted two loopkeys by accident it could be a huge fire.
A better way to do that would be a pigtail.
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Just donât own two loop keys at once. Or literally lock one up somewhere else at home etc. I wrapped my lice key in red and had a dummy to fill the other spot that was completely black.
But yes, if you connect two loop keysâŚ. Boom
Just have a short (10cm) pigtail with a male XT90 on it, and two female XT90S plugs, one for each battery. Plug it in to whichever battery you want. Itâs also an antispark power shutoff.
Yeah that would work fine as well. Little trickier to make it clean looking possibly though but Iâm sure you could figure something out
I donât know whether the OP is able to set it up with this build but the way I would go with this is to have separate chargers for each pack. I have a build with 4P, 4P, and 10P all wired to discharge in parallel but each pack has its own charger. The nice thing about this is that I can charge at low current and I use just 3A chargers. I have another build Iâm working on which will have 2P + 2P + removable 6 or 7P (the 2P + 2P will be sort of like the jump pack).
You might be charging all 3 together with however many chargers you plug in.
Not really much different than 1 giant 18P pack with 3 chargers. Which seems to work.
This is the part that can start fires:
Wasnt talking about the ziptie, was more about never disconnecting to charge which as I said offers no charge protections on the secondary pack
Yes itâs important to always charge to full with the removable pack and not be mixing voltages and yes I believe there may be some cross-charging going with the separate chargers. The lights on the ones attached to the smaller packs will get to green first but I still always leave them all plugged in.
I have a battery switching system on my board shown in the first portion of this post here:
I designed the dual loopkey in such a way that it is physically impossible to plug in both at the same time, that is the only reason why I would consider this setup safe. This is not a parallel pack situation but a pack switching situation. I personally think parallel packs have a bit too much risk involved, but there are ways that they can be done relatively safely.
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Your design is so sweet. If I was still running a double pack setup this is what I would do hands down.
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It does, as there isnât a chance of connecting them together again at different voltages. Itâs a huge risk averted if you simply never disconnect the parallel packs.
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Lots of things are dangerous with user error. My blender is a hazard if I stick my hand in it while itâs running.
Just tie the loopkey to the board. Make it impossible to use another loopkey. Itâs not that hard.
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âŚor just choose to build it a safer way, because itâs easy and cheap to do so.
Ill take risking human error vs the chance yhat at any time pack B gets fucky and then goes boom because there is no charge protections on it.
What youâre recommending is more dangerous than trusting folks to connect packs at the same SOC.
Your hyper focus on one danger has clouded your mind to not weigh the other dangers involved.
You are essentially suggesting to folks that itâs fine to charge without protections, stop it.
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Keeping the packs separate is simpler and safer. If you always have extra loopkeys around and donât trust yourself not to plug two in at the same time, there are awesome solutions like @DeadLightning came up with, that take the human error potential away 100%.
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I had thought maybe you meant if it was in the wrong mode but that shouldnât be possible either as it is still not an actual short. The current will still be going through the meter and would prevent damage. At worst, the multi meter should just blew its fuse or potentially self destruct on itself if it is a cheap one. Also that would only happen if the multi meter has two separate current circuits and youâre accidentally on the lower rated one.
I donât see how my probes could connect the way you mention, but I do think probes with a slightly different design may be able to accidentally touch like that.
Parallel batteries are dumb and unsafe.
I play with batteries every damn day and like to think that I know a thing or two about them.
Even I have done fucky wuckys with parallel packs, at the hands of complacency.
The best option is just to build one pack for one board. Multiple packs, parallel packs, charge and ride packs are all going to offer known risks (and likely several unknown risks) in a number of everyday situations.
Not everybody is 100% on all the time. Its very easy to make stupid mistakes.
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DammitâŚwill you battery nerds stop with the frakkinâ tech-talk and stick to English for us normal folk! 
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