on their Oct 19th video they said, that it works best to bottom balance the cells to 2.75 volts
then only charge them to 3.55 volts
didn't give a lot of details about how to do this in the video.
Balqon
another option for batteries would be Balqon they currently have !00 ah batteries for $110
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General Information on Lipo Batteries
The shorter the discharge (low DoD), the longer the battery will last. If at all possible, avoid full discharges and charge the battery more often between uses. Partial discharge on Li-ion is fine; there is no memory and the battery does not need periodic full discharge cycles to prolong life
Most Li-ions are charged to 4.20V/cell and every reduction of 0.10V/cell is said to double cycle life. For example, a lithium-ion cell charged to 4.20V/cell typically delivers 300–500 cycles. If charged to only 4.10V/cell, the life can be prolonged to 600–1,000 cycles; 4.00V/cell should deliver 1,200–2,000 and 3.90V/cell 2,400–4,000 cycles. Table 4 summarizes these results. The values are estimate and depend on the type of li-ion-ion battery.
Li-ion does not need to be fully charged, as is the case with lead acid, nor is it desirable to do so. In fact, it is better not to fully charge, because high voltages stresses the battery. Choosing a lower voltage threshold, or eliminating the saturation charge altogether, prolongs battery life but this reduces the run time. Since the consumer market promotes maximum run time, these chargers go for maximum capacity rather than extended service life.
The lower the voltage the more cycles you get, but it also lowers your run time.
| Charge V/cell | Capacity at | Charge time | Capacity with full saturation |
| 3.80 3.90 4.00 4.10 4.20 | 60% 70% 75% 80% 85% | 120 min 135 min 150 min 165 min 180 min | 65% 76% 82% 87% 100% |
Li-ion should never be discharged lower than 3.0 volts.
To make a 156 volt system you need 48 cells which breaks down to 3.25 volts per cell.
some manufacturers rate their batteries at 3.3 volts, other 3.25 volts.
Break in period (from one of the off brand manufactures of LiPo batteries)
LiFePO4 batteries are new enough in the market that there is not a lot of good
information available on how to maximize their lifespan. Our own experience indicates
that a gentle break-in period for your battery will help make it happy and long lived. For
the first 20 charge/discharge cycles, it is important to avoid over-discharging the battery
(below 1/2 of its capacity), and to avoid prolonged, high currents (> 15 amps). This is
just like breaking in a car. Just use it gently at first, and try to avoid sudden starts with
it, or climbing long, steep hills at full throttle, until it has been broken in a bit.
Battery Damage - LiFePO4
The most damaging thing you can do to the battery is over-discharge, allowing any cell in your battery to fall below 2.0
volts. Some cells may become discharged to that point slightly before others. So you
can't just wait until the overall battery voltage drops to a cut off voltage since by the time the battery is that low, some cells are below 2.0V. It is
better to play it cautiously. We recommend you don't let the battery pack fall below an
average of 2.5v/cell.
Absolute maximum discharge rate of 3C (30A for 10Ah battery); recommended discharge rate 2-2.5C
LiFePo4 technology does not contain any heavy metals and does not exhibit the "memory effect" of Nickel-Cadmium and Nickel-metal Hydride solutions.
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other advice:
Never Exceed 4.3v/cell, never Discharge below 2.7v/cell
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