Victron energy BMV-700 Anleitung Seite 36

6 LITHIUM IRON PHOSPHATE BATTERIES
LiFePO is the most commonly used Li-ion battery chemistry.
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The factory default "charged parameters" are in general also applicable to
LiFePO batteries.
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Some battery chargers stop charging when the current drops below a set
threshold. The tail current must be set higher than this threshold.
The charge efficiency of Li-ion batteries is much higher than of lead acid
batteries: We recommend to set the charge efficiency at 99 %.
When subjected to high discharge rates, LiFePO
better than lead-acid batteries. Unless the battery supplier advizes
otherwise, we recommend settingPeukert's exponent to 1.10.
Important warning
Li-ion batteries are expensive and can be irreparably damaged due to over discharge or over
charge.
Damage due to over discharge can occur if small loads (such as: alarm systems, relays,
standby current of certain loads, back current drain of battery chargers or charge regulators)
slowly discharge the battery when the system is not in use.
In case of any doubt about possible residual current draw, isolate the battery by opening the
battery switch, pulling the battery fuse(s) or disconnecting the battery positive when the
system is not in use.
A residual discharge current is especially dangerous if the system has been
discharged completely and a low cell voltage shut down has occurred. After
shutdown due to low cell voltage, a capacity reserve of approximately 1 Ah per
100 Ah battery capacity is left in a Li-ion battery. The battery will be damaged if the
remaining capacity reserve is drawn from the battery. A residual current of 4 mA for
example may damage a 100 Ah battery if the system is left in discharged state during
more than 10 days (4 mA x 24 h x 10 days = 0,96 Ah).
A BMV draws 4 mA from a 12 V battery. The positive supply must therefore be
interrupted if a system with Li-ion batteries is left unattended during a period long
enough for the current draw by the BMV to completely discharge the battery.
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(LiFePO
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batteries perform much
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)