Lithium batteries and alternator protection.
The six 6 volt lead-acid house batteries in my class A DP have gone bad. I am looking to replace them with 6 Battleborn 100Ah 12v LiFePO batteries. Eventually I will be adding solar. I am not look...
Forum Discussion
BFL13 wrote:This thread is about damaging your MOTORHOME alternator and using a DC to DC charger to protect it. Not sure your comment is relevant?
"Ref overcharging via the 7-pin, a lifepo4 (with a properly functioning BMS) would have to be subjected to =>14.6v continuously for days/weeks at a time to be overcharged"
According to at least one article on LFPs, any time at Vabs past when the batt is "full" reduces its expected number of cycles. This might be in dispute by the various experts. No info on how many cycles lost. Longer time = more lost?
Usual? story is wait the 20 minutes like BB says for balancing but no real harm done by leaving it at Vabs for ? time days/weeks.
With alternator charging, drive time keeps time at Vabs short. If the batt is not run down much overnight and you drive more next day, does that add more hours at Vabs, which would be reached quickly after starting off?
That same article says Vabs can be anything like 14 vs 14.6 it just means it takes longer to get the batt full, so hard to know when it is full and you are now into overtime? I don't know. It is all a mystery how it really works.
He also mentioned the rated "3,000 cycles" was done by running the batt up to full and immediately discharging it so there was no time ever sitting at Vabs when full. He claims that if you did the rating like a real RVer would using some time at Vabs when full, you would have fewer cycles as a result.
IMO that does not matter if you only get 2,000 instead of 3,000 because many Rvers will only do 500.
Oops I forgot--I am not allowed to talk about LFPs on here because I don't own one. Sorry! :)
