Lithium batteries and new solar charger
I am replacing my 4 6V batteries I think 2 lithium, have never been impressed by the 30A PWM charger for my 600W solar, probably my fault for using 8 avg wire on a 9m run. Thinking if I get a Victron ...
Forum Discussion
full_mosey wrote:BFL13 wrote:
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But resting full is 13.6v so 100 x 13.6 =1360 watt hrs so it is confusing? Whatever, Battle Born claims the 100AH batt has "2 to 3 times the power of the same size lead acid" batt.
"Power" meaning watts? Watt hrs? meanwhile a 100 AH 12v FLA has a resting voltage of 12.73 when full so that is 1273 watt hrs.
Beats me how 1360 is 2 to 3 times 1273. I am told this would all make sense if only I owned LFPs myself, but do you need some kind of New Math too? :)
Easy, Watt-hours are energy, not power.
Which one can produce all of its energy, 100Ah, in the shortest time?
Put another way, LFP has the same size fuel tank but more horsepower and can work faster.
If the FLA is pushed to work faster than 5A, less work gets done. The LFP doesn't care because there is virtually no sliding scale of work produced based on how slow or fast it gets done.
HTH;
John
Sounds a bit like this from the Relion LFP blurb:
--Constant Power-- Full power available throughout discharge. Voltage does not drop like lead-acid.
Are they using "power" correctly? I can't keep the physics stuff straight. Grade 6 math I can do, but Physics was in Grade 7 I guess :)
The high discharge rates with LFP (and SiO2) table does show the time it can do the high rate is shorter the higher the rate somewhat like an FLA has less capacity in AH with a higher amp draw.
The 100AH SiO2, eg can do 5 amps for 20 hrs, 62 amps for 1 hour,105 amps for 30 minutes, and 175 amps for 15 minutes, all with an end voltage of 9.6 volts
