In the early days of my electric discoveries I balanced the small pack with a pair of Blinky bleeders. This was fine for 6 or 8 brick-sized batteries from time to time, but then difficult and cumbersome when the pack grew to include another 12-14 bricks.
In resolution I purchased the Version 4.0.8 of the LVC/HVC/Parallel Adapter
last year (June 2010) just as I was starting the Going to California
trek. The truth is that I didnâ€™t have the means to complete the assembly on the road, and it remains boxed and unassembled to this day. The reality is that the last time I ran out of power was on the last day â€“ just one block shy of the Amtrak station after traveling 173 miles.
When I returned to Redmond the pack was divided in half, electing to keep 18 bricks on the bike for commuting. Today I have a total of 72 bricks (15S24P) in preparation for the next big odyssey
. With so many lilâ€™ lipos the Question of Balance
is an intriguing one.
A cursory study suggests that I can parallel the JST-XH connectors for the balancing application. The new BMS tendered by TTPacks appears to manage this with increased ability. However I cannot afford purchase a BMS for every brick, and even if I were to divide 72/4 to equal 18 â€“ the cost is beyond scope.
So we return to the Question
. Certainly I would like to level the voltages across the pack, and it is easy to understand that cells in series could be of different potentials. What happens though if we were to parallel these cells, first as groups of 3 or 4, or perhaps more? Should we limit this parallel process to the clustered series? Example: 5S1P x 9; with 3 in series it becomes 15S3P == 3 JST-XH connectors in parallel with 3 bricks each. What prevents us from tying all the cells into parallel? Would the resulting disparities of potential resolve themselves?
Admittedly padded clothing and a face shield might be required when creating this linkage if the individual cells were way out of balance. Though once hooked up, wouldnâ€™t they float together in parity? What if we left them that way whilst charging/discharging?
If I ran in the fat of my pack, never too high and never too low with cells linked in this manner â€“ would that preclude the need for a balancer?Reference two interesting balancing concepts:
Deeply curious, quite possibly really denseâ€¦
â€¦and somewhat Moody