I have converted my ATV to electric and it runs well with my lithium 60v packs of 18650 battery pack..I needed a longer range so I upgraded my old small lithium battery to 60v 100ah 50A bms lifepo4 battery it runs well at first but after a kms.it tripped off and need to reset it again..I thought I need a bigger Bms so i changed to big BMS 150A continous and 300A maximum .but still the same it will trip off after some distance..but unlike the small 50A Bms this time it will just shut off and the power will turn on again.but will continue tripping off and on when it started to trip off..i returned my old batteries and all will be back to normal..
if a battery comes wiht a BMS with a certain current limit, it generally means the cells in that are only capable of, at best, that current (and that is realistically probably pushing it for many cheap packs).
So going to a higher current BMS means the cells are then being abused beyond their ability to deliver current, and so their voltage sags under that load, often so far that the BMS low voltage cutoff LVC is triggered.
You'd need to replace the cells *and* the BMS (hence, the entire battery) with ones that can actually handle the current, for this situation.
The interconnects inside the battery between cells are probably also insufficient, and would have to be replaced. Any fuses, connectors, circuit breakers, etc., probably also have to be replaced.
If your old battery works wtihout this problem, it is actually correctly made for the load you're putting on it. (you can check it's specifcations / manual to see what it's intended to be used for).
i am already confuse will I need a new controller since my controller is only 60v 1000watts 45A capacity and my motor is 60v 1000watts..
If your controller is only 45A, that normally means battery current required. (you'll need to check it's manual or specifications to be sure). If that's the case, then a 50A battery should handle that fine. If it doesn't, it's a pretty crappy battery, and unable to deliver even part of what it says it can, so it's either old, worn out, damaged, or built wrong or from insufficent parts, or in the worst cases from recycled garbage cells (not uncommon) that shoudln't be in a functioning battery anymore.
if I need to change the controller how many watts and Amp will i purchase?to match my new Battery n Bms and Big tires.
You'll actually need to do it in a different order.
first, you calculate how much power it takes to do the job you want, under your worst-case riding conditions, at the highest speed you must go, at the highest weight you'll ever have (you, atv, anything you carry, motor, battery, etc), at the acceleration rate you require.
Then take that power and find a controller (and motor) that can do this, with your gearing / wheel size. / etc.
*then* you find a battery that can supply that power, continuously, for as long as you need it to.
by the way my rear wheels are big 20 inches tire I took from my car. i am thinking that the big tires makes the controller draw its maximum amperes that makes the system trips off? need some advise on this?
Bigger wheels, for the same drive system, loading, riding conditions, etc., will require more current to do the same job as smaller wheels, because the size increase effectively shifts to a higher gear, providing higher speed but lower torque.
If it's not a hubmotor, but a chain or belt drive, then to compensate for it, if you don't need the full speed that wheel size provides, you can simply change your gear ratio from the motor to the wheel drive axle to have a bigger rear sprocket or smaller front one (usually smaller front is not possible or advisable for various reasons, but we don't have any info on your setup).
To see how this works you can use any of the online calculators or simulators for gearing vs speed vs torque on any kind of vehicle. If you want to experiment with them and learn more details of how the electric side of things works, you can use the ones at ebikes.ca but it does require some time to read the whole page and learn how to use it, then experiment with it until you see it.
