ProgressiveRC 6 PowerLab - Manual (Page 56)

Other information
Charging tips
General information
Because PowerLab’s cell balancing technology monitors individual cells, you don’t
need to cool a pack before charging it. Go from flying to charging to flying again
without waiting.
Cells in a pack have different voltages when they are discharged. PowerLab 6
balances (equalizes) cell voltages while it is charging the pack. REVOLECTRIX
chargers provide the highest available balance current in the industry: up to 1A, and
now customer-adjustable.
During charging, cells that charge the fastest are the weakest cells in the pack. At the
end of charging, cells with the highest voltage are weakest. This happens because
weaker cells have lower capacity, and they charge faster than stronger cells.
If PowerLab 6 displays LOW VOLT RESTORE, the pack was over-discharged during
its last use or there is an issue with the wiring of the pack(s) connected. The charger
will attempt to repair LiPo cells measuring between 0.5V and 2.7V, or A123 cells
measuring 0V to 2.0V. To avoid additional damage to restored cells, do not over-
discharge a repaired pack.
CAUTION: LOW VOLTAGE RESTORE mode is designed to prevent fires
when packs are damaged. If you see the PowerLab go into this mode of
operation, allow the pack to charge for a few minutes, then stop and re-start
the charge. But do not continue the process. Locate the real cause of the
problem. Continuing to force over-ride LOW VOLTAGE RESTORE can result
in fire.
By definition, end-of-life for a LiPo cell is when the cell can only be charged to 80% of
its original capacity rating. The number of charge/discharge cycles a cell undergoes
before reaching end of life depends on several factors, including cell quality,
discharge rate, internal heat generated during use, and other parameters. Cells in an
older pack may be more out of balance, but PowerLab 6 will still balance them to
within 6mV by the end of charge. For this reason, it may take longer to balance older
packs. The charger may show FUEL=99% for several hours while it is balancing a
high capacity (3Ah and up) “veteran” pack that is severely out of balance, but User
Presets might be set to stop balancing after a preset time. Often, the last few millivolts
of balancing take a very long time and do not significantly improve overall pack
charge or performance.
Charging packs
You can top off packs, or remove them when they are partially charged. There is no
way to damage a pack when using PowerLab 6. (The only exception to this is if you
are using Safe Parallel Adapters and you accidentally connect two packs having
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