Raj174 wrote: »
I have read a good bit about the Stark Power batteries. Built in BMS is a plus and the batteries also shut down at 20% capacity, which is very desirable in the event of improper low voltage disconnect settings on the inverter. Series connections are always preferred, but I would say especially for LiFePO4. The Stark Power 12 V batteries are actually a series/parallel battery pack with management. I think that it would be better if all the cells in the system were under the same management, i.e. 100 AH battery instead of two 50 AH batteries (less headache checking battery voltage differences), but that's just me.
If you do set up 2 in parallel make sure your cable lengths are the same and monitor the voltage of the batteries to make sure they don't drift apart. The only other thing is charging voltage. Although Stark Power says it is a drop in replacement for a lead acid battery and has over charge protection, I would not use lead acid charging parameters on these batteries. I would charge at 14.1 volts and set float to a little lower than that. I would not discharge to lower than 12.4 volts, even though the management will shut the battery off at 20% capacity. Just my opinion.
DoubleDD wrote: »
Thanks for your thoughts.
I was planning on wiring the batteries as outline in the pic below so I could add additional batteries easily. All wires would be 2/0 welding cables (18") from battery to post. I'm still trying to find the best MPPT solar charger for this application. Any suggestions?
Wouldn't the individual BMS keep each battery in sync? By setting the cutoff for discharge at 12.4 volts, what would that work out in % of used AH in a 50AH battery.
Would you recommend going down the path of LifePo4 GBS/Winston cells with a central programable BMS instead?Attachment not found.
Re: Low Cost Lithium Battery Motorhome Conversion
Six Month Report:
All is well with my Lithium conversion everything is working perfectly.
These long days show my DoD of only 25 Ah over the short night time.
Battery is usually fully charged by 9 AM.
With only 100 Ah capacity it more than covers what the 4 golf cart batteries did.
I would expect that I would need 1000Ah of lead acid to give the same charge/discharge performance as these lithium do.
With no maintenance on the lithium battery, its easy to forget you even have a battery just perpetual free electricity always at the proper voltage.
I would definitely do the conversion again and am now sure that I don't need any additional capacity.