i don’t know details but know it depends on the size of the cell of course. I charge an 8ah pack at 8amps so im on the cusp I think but double that, if my charger could do it, I’d have a hard time getting to that top of the charge. what I was reading made it out like it would take as long to get to a full charge even if you do it speedy as going speedy it blasts through the cc part of the charge but then the cells will have to sit for much longer on the later cv part for them to actually hold the energy. something like that.
I was just trying to show @ralphy that the mah reading on his charger did not necessarily mean that there is anything wrong with his battery cells. As long as the pack charges to fulll voltage, it’s good.
haha. as long as the pack charges to full voltage it’s good! out of context it sounds like some crazy battery advice. I’m imagining some nubie with their totally dead and abused battery sitting patiently at the charger.
have you ever tried to revive beat up or really low voltage cells? If any cells have a voltage that’s strangely low I call it done and don’t bother . anything that wont pop up to 3 volts by the next day. if it wont I give up on it. similarly my cells with holes in them show really low voltages and I give up on them of course
you’ve got your battery amps at 25 and motor at 40 @ralphy. that’s very low. especially with the voltage you’ll be using at 6s…that’s like 25 x22 max power in. 500 watts. subtract losses and maybe 450. you might be really disappointed. you could increase the battery max amps to 40 at least and the motor…dare I say 200!
if you live near san Francisco Ive got a bunch of those cells Im getting rid of and you could bump it up
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It’s a 12s 2p setup @hummie. So I’m happy with the power output. I will look into your advice on those settings and improving performance.
I didn’t know you had these cells I’m in Miami. I dropped like 150 bucks on 24 cells from imrbatteries in Texas.
As far as fast charging like ions yes the first 70% can be done fast. That’s how the Tesla supercharger stations work. They fill the cells up in 20min or so to 70% capacity . It’s pretty cool.
you’re setting the amp limit at like 60 percent of the cell’s stated peak discharge limit. I guess you could make the cells last longer that way but I’d rather have the performance the few cells you have are capable of.
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Fast charge just means you charge at Constant Current. Once you reach the CV phase the charger stops. You can do this at literally any current up to whatever the max current for your cells is. I usually do mine at 1c
The capacity you put in is always higher than the capacity you discharge. This is because your charger is not 100% efficient and there are some losses in the wires, etc. This also happens because your charger will balance the cells which pretty much entails charging the battery and discharging the cells with high voltage through balance leads until all of the cells are at the same level, the charger does not take this into account when giving you the amount of energy you put in. A simple way to see this is by charging not balanced and then balanced and you’ll see the latter takes in more capacity even if they end up at the same voltage
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My Lipos packs are rated for 25a charge. I charge them at 5a so I’m guessing that would not be considered fast charging.
.I wouldnt say fast charging “just” means you charge at constant current, it also means you’re charging at a high current.
@Namasaki what c rating are your cells?
Ok, ya I guess that statement could be taken wrong. I meant within the normal amount of charge time.
im starting to sound like grammar police.
can you find your lipo charge rate? it seems rare.
They are 5000mah 60-120c Lipos with 5c charge rate.
weird my flightmax 8ah with 30c have a 5c charge rate as well. so what’s the math for this stated max madness. 5 times 5 for you. 25amps.
For him its 25 for you its 40. And fast charging really is just cutting off the cv stage. There is no current defined that you should charge at for it to be fast, all companies do it at different rates.
EG Tesla does 1C I believe, Android phones do 2C, Lipos can be done at 5C, liions at 1-2c.
It really depends on the application. The one thing they all have in common when they say fast charge is that they cut off the cv phase
The whole pack is running two vesc. Are you sure I can push that little pack to those limits per vesc ?
No. You would kill your cells. 25A per vesc is 50A total. Your cells are only rated to 20continuous and you have two in parallel which means 40A total. Your settings are fine, you might be pushing them a little
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I figured it was pretty much maxed out because I can’t stay on the board if i hit full throttle from a stop.
Top speed is at 23 mph and I’m 180 lbs
I used to get 26mph with a 16000mah 12s1p lipo.
is your computer a Mac or Pc?
Pc dude, i hate the fruit… surface pro3
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This is what i was talking about, at first I didnt know it but i think it later on becomes clear that you can get ‘varied’ amount of capacity when discharging.
Discharge rate and temperature influences this, so the cells are not as ‘linear’ as we would like to think 
sorry for my math above I thought we were working it out for one motor.
As you say @okami, and I wonder how well a lipo being used under the typical low rate of discharge for its stated ability on a board will compare to a li-ion being pushed further towards it’s discharge limit in capacity and also life cycles. but can’t you get really close discharge energy to the input energy if you draw at low amperage? the conversion from chemical to electrical energy is probably the most efficient thing on the board possibly
The word “fast”…can mean anything I guess but in my mind a fast charger is one that would charge fast. 1c rate is pretty fast.