bobc
10 kW
I guess the different battery types, chemistries, constructions, manufacturers etc will all have slightly differing characteristics - the data above is a little hobbyking lipo brick, totally raw data, and you can see the Rs is about 165mohm when the battery's full and reduces to less than half that when it empties.
And yes, any BMS that looks at each individual cell can prevent over-discharge and overcharge. The claimed advantage of the bottom balanced stack is that it is considerably (if not completely) less able to destroy itself (by cells with some juice left reverse charging the flat ones in series), because they all go flat together.
This actually suits one of my projects, and sounds like a sensible approach if you're going "no BMS". But for general ebiking a classical BMS is the easy solution to live with; and it is electrically cheaper and easier to make a dissipative top balancer.
Somebody going "no BMS" could very easily make a bottom balancing circuit to plug into each cell individually on the balance lead (just 2 pins at 0.1") and discharge it at 2A down to (say) 3.000V. This would be easier and safer than the OP's suggestion of unwiring the whole battery stack and placing every cell in parallel....
And yes, any BMS that looks at each individual cell can prevent over-discharge and overcharge. The claimed advantage of the bottom balanced stack is that it is considerably (if not completely) less able to destroy itself (by cells with some juice left reverse charging the flat ones in series), because they all go flat together.
This actually suits one of my projects, and sounds like a sensible approach if you're going "no BMS". But for general ebiking a classical BMS is the easy solution to live with; and it is electrically cheaper and easier to make a dissipative top balancer.
Somebody going "no BMS" could very easily make a bottom balancing circuit to plug into each cell individually on the balance lead (just 2 pins at 0.1") and discharge it at 2A down to (say) 3.000V. This would be easier and safer than the OP's suggestion of unwiring the whole battery stack and placing every cell in parallel....