So I've read pretty much every thread I can find here about the SOK and Big Battery Powerblock options, along with watching Will's recent video on them and reading through this long thread on Big Battery getting caught making false charging claims (located here for anyone who hasn't seen it https://diysolarforum.com/threads/is-big-battery-full-of-crap.14319/).
I'm in the market for a prebuilt lifepo4 pack, and for a while was considering the Battleborn, but then became interested in the SOK and Big Battery offerings seeing how they seemed more closely aligned with something I could build myself (and possibly service in the future), plus much lower cost. I do plan at some point in the future when I have time to build my own pack, but for right now I'm working backwards from a deadline and I need a working battery I can just install and use as my time is allocated to other projects.
With that said I'm still interested in the Big Battery offering, since it looks like it's a decent build once you account for them owning up to their mistake and fixing the BMS issues so all units will have the proper temperature charging profile. Here are the two options I'm considering
Big Battery 24V 170ah Pack (x2) (8160Wh)
$1350 (x2) = $.33 cents per Wh
Max Discharge Current: 175A
Max Charge Current: 100A
or
SOK 12V 200ah (x2) (4800Wh)
$1030 (x2) = $.43 cents per Wh
Max Discharge Current: 100A
Max Charge Current: 50A
My plan is to use a Victon 24/3000/70 which on the inverter side can output 2400 continuous watts with surges as high as 6000 watts. I think for my use I'll probably end up near the 2400 watt mark sometimes with surges into the 3000-4000 watt area briefly.
From looking at the SOK Max Discharge Current it appears than I'd be right at the 100A discharge limit to pull 2400 watts with my inverter, but anything beyond 2400 watts will be beyond the capacity of the SOK battery. Is my math right here? And as for charge current with the SOK I'll be limited to a max of 1200 watts, which will be fine for my solar charge capacity, but my alternator charge capacity will be around 1440 watts, and my shore charge capacity around 1680 watts. So it looks like the SOK would require me to scale back my charging plans for DC-DC as well as shore.
Based on all of this my questions are...
1) Is my math on the SOK charge/discharge limitations correct? Will I be limited to a max of 2400 watts from my inverter for discharge and a max of 1200 watts for the charge from DC-DC and shore?
2) Given the low cost of the Big Battery pack, plus the decent build quality and cells (with BB fixing the low charge temp error they made) is it really the best option given my charge/discharge needs all things considered?
3) Are there any other prebuilts on the market you'd recommend that are at least as good as the SOK/Big Battery in terms of cost and quality?
Thanks!
I'm in the market for a prebuilt lifepo4 pack, and for a while was considering the Battleborn, but then became interested in the SOK and Big Battery offerings seeing how they seemed more closely aligned with something I could build myself (and possibly service in the future), plus much lower cost. I do plan at some point in the future when I have time to build my own pack, but for right now I'm working backwards from a deadline and I need a working battery I can just install and use as my time is allocated to other projects.
With that said I'm still interested in the Big Battery offering, since it looks like it's a decent build once you account for them owning up to their mistake and fixing the BMS issues so all units will have the proper temperature charging profile. Here are the two options I'm considering
Big Battery 24V 170ah Pack (x2) (8160Wh)
$1350 (x2) = $.33 cents per Wh
Max Discharge Current: 175A
Max Charge Current: 100A
or
SOK 12V 200ah (x2) (4800Wh)
$1030 (x2) = $.43 cents per Wh
Max Discharge Current: 100A
Max Charge Current: 50A
My plan is to use a Victon 24/3000/70 which on the inverter side can output 2400 continuous watts with surges as high as 6000 watts. I think for my use I'll probably end up near the 2400 watt mark sometimes with surges into the 3000-4000 watt area briefly.
From looking at the SOK Max Discharge Current it appears than I'd be right at the 100A discharge limit to pull 2400 watts with my inverter, but anything beyond 2400 watts will be beyond the capacity of the SOK battery. Is my math right here? And as for charge current with the SOK I'll be limited to a max of 1200 watts, which will be fine for my solar charge capacity, but my alternator charge capacity will be around 1440 watts, and my shore charge capacity around 1680 watts. So it looks like the SOK would require me to scale back my charging plans for DC-DC as well as shore.
Based on all of this my questions are...
1) Is my math on the SOK charge/discharge limitations correct? Will I be limited to a max of 2400 watts from my inverter for discharge and a max of 1200 watts for the charge from DC-DC and shore?
2) Given the low cost of the Big Battery pack, plus the decent build quality and cells (with BB fixing the low charge temp error they made) is it really the best option given my charge/discharge needs all things considered?
3) Are there any other prebuilts on the market you'd recommend that are at least as good as the SOK/Big Battery in terms of cost and quality?
Thanks!