RV and vandwellers wiki

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3.42v/cell) could help avoid LVD, making 35% of the cells' capacity unusable. 24v banks in general could preclude alternator charging, however. Pro:

• About half the cost of LFP for the same Ah capacity
• widely available

Con:

• overcharging or physical damage can cause a runaway condition (ie fire)
• voltage mismatch of 3S to nominal 12v systems

===== health ===== Batteries are typically replaced when they can no longer provide 80% of their rated capacity. This requires fully charging, then discharging at the 20-hr rate (C/20) until the battery is depleted. This is impractical with house batteries that are in actual use. Because of this, we use indirect methods to assess battery health. Tail current (aka endAmps, finishing amps) for healthy lead batteries is typically between C/200 and C/100 (0.5A to 1.0A at Vabs for per 100Ah of capacity). If tail current cannot get down to 1A we can assume there is trouble. The rise to absorption voltage is rarely useful in the field since:

1. solar charging alone is rarely able to hit charge current maximums
2. alternator charging is rarely able to hit Vabs

People charging off larger DC-DC chargers, shore power, or generators may be able gauge the speed at which the bank comes up to Vabs.