I guess that’s about the same weight as 2 of these 20 Ah lipo cells. Each is 2.5 KG
@taz how much would it be to for a 18650 battery that gives around 25ish miles with on/off road riding, riding 20-25mph most the time, 8085/170 kv motors. i am considering getting some more batteries for more range, i carry a bag anyways and my riding buddy will have to swap batteries as well. i have been using 4 6200mah lipos and am at 3.8 per cell when done with 12/13 miles of “fun” riding. i think it was thread you had made that i found earlier on my phone about 18650s on their trampa, but i havent read to many others that run them or anyone that makes any for a monster box,
A 12s8p with 30Q cells is 24Ah.
So if you get 12-13 miles out of 12.4Ah you should be able to get 25 miles out of it.
That is the maximum amount of batteries you can get inside the monster box and still have room for a BMS.
Cost depends on your builder.
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I finally ended up buying 2X HRB 22000 from here
I also bought a balance charger as well as a 15amp fast charger that i’m going to hook up to a BMS that i’ll either put inside the box or create a 3D printed module.
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All the way. If it’s not a bms with 1.5A balance current, than you can’t expect much balancing from it @15A charge current. I think it’s more practical to use the bms to not overcharge one cell if you charge with 15A but the balance charger for actually balancing the packs.
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Yes! That’s the plan. First time working with lipos and you weren’t kidding about the shitty connectors and the hassle of all the cables.
The only thing that I need now is the blasted board which is on back order since the last month.
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@Andy87 I didn’t really understand what you meant the first time. Now I kinda do.
This is the rating of the balance charger I’m using.
When you said 1.5 A did you mean for single cell or all 12 cells ?
I mean single cell.
It’s usually always stated for single cell on bms data sheets.
I‘m not quite sure in which context it was because well a bit a time ago 
But in general I think my thoughts about it was that if you charge with high amps your bms has less time to balance as the charge process is faster. Yes your charge current with a cc/cv charger goes down the closer it’s at full charge but non the less there is less time to balance if you charge with 15A or with 3A.
To don’t get a shit storm…
There are different types of bms.
Some just cut off (that’s the case if the data sheet doesn’t tell anything about balance current?
There are bms which start at a fixet voltage ( for example 4V) to balance and do this till one cell reach 4.2V
There are bms with active balancing, which means they switch off the charger if first cell reach 4.2V or slightly over. Than drain the higher cell below 4.2V than switch on the charger again till a bit over 4.2V and start to drain again. This continues till all cells are at one voltage.
And there are bms like the smart bms which charge your pack up till you hit 4.2V at one cell than switch off and start to drain all cells which have a higher voltage as the lowest voltage cell in the pack till all cells have the same voltage.
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So the lipo charger I have can only charge these two batteries simultaneously at 2-3 amps each lol. Now that I’m carrying the batteries outside the box , I can use the lipo charger and charge overnight.
But what happened was that last time I charged up to 100 % with the fast charger but then drained it to 90 and tried to balance charge but now one cell is just stuck at 4000mah and my charger can’t balance it.
You can charge a single cell through the balance leads. You’ll have to keep the amperage low bc balance wire gauge and all…
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