Molicel P42A cell discussion

[b264]

@bwahl602

Most of us use a BMS only wired for discharge (no over discharge protection)

To be clear, Bill is referring to something like this

@b264

BMS bypassed with loopkey and discharging with lights/accessories circuit

@Battery_Mooch

1. When you say “parallel charging” you’re talking about paralleling the chargers, not the packs? That’s a verrrrrrry bad idea for many chargers and I strongly advise against it. But, having said that, there might be ways to do it universally with some additional components on the charger outputs.

So much depends on the particular charger and its circuit though.

Which chargers did you successfully do it with?

@murdomeek

a lot of people in the electric unicycle community does this. Just a straight parallel wire splitter into their wheel
Seems to work just fine for them

I have done this a lot with the MDA 4A float chargers as sold by Evolve, Metroboard, enertion, etc…

@Battery_Mooch

Using any two different chargers or the same model of a specific charger?

I’ve done both. Though anecdotal evidence proves nothing… …it’s highly dependent upon the specific charger’s circuit as you noted above. I also had a 10A fuse on each charge port separately.

@murdomeek

Mind you that they only do this occasionally on long distance group rides. They just charge regularly at home if they don’t need to be fast.

And yeah, this, I rarely do it. Only if I need a full battery in a jiffy

@Battery_Mooch

Conductor current limits have to take the insulation temp rating into account along with what’s acceptable for power losses. You can run a wire right up to its fusing current level and it will still work. But operating a wire at just below the melting point of copper is typically not a great thing to do. This all means that 18AWG wire could be rated at 2A for voltage-drop sensitive applications all the way up to 20A or even higher for pulsed applications where power losses aren’t an issue and silicone or Teflon insulation is used. Let’s talk…maybe there’s some testing I can do with a bunch of 12” lengths of different wire and some nickel strip.

We would love to hear more about this

Conductor Current Ratings [SRO]

I’d like to make an easy-to-find list of current ratings for esk8 use. If anyone has edits, corrections, experience, or thinks it can be better, please describe what you think should be changed. Popular esk8 sizes in bold. [current_capacity] This chart is labeled for continuous and not instantaneous. You can pretty much double every number for instantaneous, for a couple seconds or less. search keywords: wire, AWG, size, nickel, current, ampacity, hot, melt, battery, amps, amp,…