I’m thinking a full 12S charger would be the way to go. Then we can leave the packs fully connected and charge through one port. The balancing ports will be big, but that’s the nature of a 12S battery
Thinking something like this. With the 3KW config, it’s about a 2.5 hour charge time.
The only thing with that charger is you still need a power supply. An AC/DC charger would be the most convenient and more cost-effective, I’m currently trying out this these ones
There are a few drawbacks to keeping all the packs in a certain size case. One being versatility and the other being cost. Ultimately it would be nice in the future, but then you need to get two different sets of batteries for different weights ranges. Right now I’m working on a case that will universally except different battery type and setups. Then again it’s not going to be perfect for any of the setups because it’s trying to accommodate all of them.
I have used an adaptor before to balance charge 2x 6s battery split charged through a single 6s charger. As far as I know, you do not get a true balanced charge.
It would be ideal to put in a single plug and charger but you would need a minimum of a true 24s balance, would it not?
Graupner make some chargers which have been recommended, but I don’t fully see their advantages over my dual charger at 1/4 the price.
Yeah, with the one I linked from Amazon, you do need some DC input - but I’m sure we can find something relatively cheap. When I look at the others, I’d take 1 charger for a full 12S pack with balancing at 1350W vs having to split across multiple 6S chargers and/or a 350W charger - which would be 4x slower.
I charge my Tattu 6s 22000mAh with a 1000 W 30A charger, powered by a 24 volt 1200W 60A power supply…
My batteries could be charged with 1C-3C max 5C…
If I charge only with 1C the 22000mAH 6s pack it is already charging with 22 A = witch equals to 1 hour charging. If my power supply had only 12 volt it would need double the time.
If my charger model is on sale i would buy a second one to charge two 6s 22000mAh packs in 1 hour.
To have an idea as to how powerful your charger has to be…
Wattage is calculated by measuring the voltage and amperage of a circuit and then multiplying them together:
Watts = Volts * Amps
If you want to charge a 22000mAh 6s pack at 1C. How many watts does that require? We know the voltage of the battery and the 1C charge rate is 22A.
Watts = 6s * 1C = (25.2V) * (22A) = 544.4W
So the charger will be outputting at most 544.4W. I say most because the voltage of the battery is changing the whole charge cycle. It will likely start in the mid 22V range and will finish at 25.2V. So in order to calculate the max wattage needed, I use the max voltage involved.
My future additional battery pack will be a Tattu 6s 28000mAh x 2 - to charge these in 1C mode and in one hour you would need a charger with ( 6s*1C = 25.2V * 28A= 705.6W ) at least 705.6 watt and 28 A per channel!
In conclusion the wattage plays a crucial role in charging. Don’t forget to take it into account as you choose your charger and power supply.
You can also charge your lipo pack with 0.5C or 0.2C in the case you have a less powerful charger!
It just needs more time…
Wouldn’t you be better off using the Van’s motor to be charging your batteries… Using a cigarette lighter plug to power supply>>>>120volt out to regular Li-Po battery charger— solar would be too slow IMO
(and keep them close to the door so you can pull them out if they start burning)
The problem with DC is finding a power source that is powerful enough and isn’t super expensive. I bought 2 500W DC chargers and I hooked them up to a 12V 1000W ATX computer power supply that I modified (very common application in the RC community). My chargers support the 12V DC input just fine but to take full advantage of their 500W capability I think I will need a 24V input. They work fine with the 12V input just slower.
My chargers are ISDT SC-620. I’ve seen lots of good reviews on them. $60 each on eBay. I charged my smaller lipo packs with them and I’m happy with them so far.