What is the Best Battery Charging Solution?

Have you tried to charge just through DC ? Have you speculated how it would be to charge your main pack from a weaker pack while outside?

Not sure if I understand, but charge through DC means you need an extra power supply or a car battery. Charging with an other battery on the outside like a powerbank? Never thought about that.

I have a 10s balance battery charger. So I just plug in my balance leads and the main power I charge at 3.5 amps it goes full charge in about a little over an hour. But u also only go about 50% on the battery before I charge. About a 7mile ride takes 3700mAh and I have a 9s4p homemade 18650 battery that has a max power of 8200mAh. 9s you may ask? Well it was 10 but I had a bad cell so I just hacked it off and called it a day.

Yes, you got it right. A powerbank to carry along

I think this is not really a good idea, because when you connect an extra battery to fill the onboard battery it will just flow from one to the other till both batteries have the same voltage, so you can not charge it completely.

This is why you would need a step down module and design a pack that has higher voltage than your board’s pack…

If you got 6s board battery voltage, then choose 8s for powerbank, to include the 1.5v drop from the lowest voltage point it will have (about 26.4v in my case (3.3v x 8))… if you subtract 26.4 - 1.5 = 25.3, which would translate to about 4.21v for 6s battery… which would be just great.

Though, in my opinion, this only works great if you got plenty of laptop batteries (cells) or you got some other odd battery which can not deliver a lot of amps (to be used as the main battery)…


So yes, you would not connect it directly… that is probably not a good idea… someone has to find a source how much amps does flow from one battery to another in such a scenario…


Another option I discussed is to use a current limited step - up module. This would enable to use all sorts of laptop chargers or just a smaller voltage powerbank, to step up the voltage to the desired charge voltage.


I know not many is gonna go this route… I just like the idea about using both laptop batteries and also be able to charge my board elsewhere… without actually always taking the powersupply with me… if the module weights around 200g, that is not a that big burden to carry with you…


Basically, all smart balance chargers are voltage step - up modules… they take less voltage and ‘boost it’’ to higher voltages levels. That’s also why there are usually some cooling as things get hot there.