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SOK LiFePO4 specs: 100Ah vs 206Ah

SteveSS

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The SOK website lists basic specs for each of their batteries. But, apparently the only place you can currently download detailed spec sheets is the SOK Facebook Group. I've attached the spec sheets for their two original 12v batteries (100Ah and 206Ah). Specs sheets for their two newer models aren't there yet.

IMPORTANT NOTE: both of these 12V batteries have the SAME max charge and max discharge limits. Those amp limits double with two batteries in parallel. However, I see a lot of folks assuming a single 206Ah battery is equivalent to two 100Ah. That is not the case. To power a typical 2000W inverter, you need at least two of these batteries, either two 100Ah or two 206Ah. The 206Ah gives you twice the storage capacity, but not twice the amp delivery rate. Storage capacity is still an important feature. I bought two of the 206Ah batteries to help ease recharge anxiety. So far, I like them a lot.

A couple things not clear in the spec sheets:

Under Balancing Voltage it says <14.4V. I found that odd given many BMS balancing systems only begin to balance at about that voltage. I asked the question on the SOK FB group and got an answer from the SOK rep. They said the SOK BMS does continuous balancing up to 14.4V. Apparently it's a real thing, but I don't know how it compares qualitatively to other balancing systems.

Although not listed in the spec sheets, the SOK rep also told me the BMS over-current cut-off is 130A. That's well above the recommended operational max of 100A. They said the 100A value was intentionally conservative. You should still use 100A for sizing your system and in daily use. It's just good to know there is some wiggle room in case you accidentally over shoot at times.
 

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  • SK12V100-0915.pdf
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  • SK12V206-0915.pdf
    1.1 MB · Views: 296
Thanks for posting these. For those of us that don't have Facebook accounts, it's so annoying when companies choose to support their products on Facebook instead of their own website.</rant>

The nice thing about using two batteries with a 2000W inverter is that it works in either parallel or series. Two in parallel is of course 12V with a combined discharge of 200A. 2000W / 12V = 167A which is obviously less than 200A. Two in series is 24V with a discharge current of 100A. 2000W / 24V = 83A which is less than 100A. So good either way.

I have two 206Ah in series with a 2000W inverter. So far I've only had it up to about 1500W and only for a minute or two but it worked just fine.
 
Yay, other SOK 12v 206ah owners!

Question for you both: what are you using to charge your batteries? What is your charging configuration/methedology?

I am struggling to find good information about charging these bad boys outside of the specs noting a 40a recommended charge rate. Most of the chargers I see on the market are between 1a - 10a and I don't feel like a 480hr to 48hr charge cycle is going to be fun (2 x 206ah SOK batteries).
 
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When I first got my two 206Ah SOKs I ended up putting them in parallel and charged them using a Victron Blue Smart IP67 charger which does 12V @ 17A. This was to get them to the same SOC in preparation for putting the batteries in series. It took about 12 hours but I only had to do it once.

Now they get charged using a Victron Inverter/Charger which is setup to charge them at 40A. If I start charging when the batteries are down to roughly 30% SOC it takes something like 5 maybe 6 hours (not sure exactly) to charge the two in series. Soon I'll also be charging via solar.
 
The SOK website lists basic specs for each of their batteries. But, apparently the only place you can currently download detailed spec sheets is the SOK Facebook Group. I've attached the spec sheets for their two original 12v batteries (100Ah and 206Ah). Specs sheets for their two newer models aren't there yet.

IMPORTANT NOTE: both of these 12V batteries have the SAME max charge and max discharge limits. Those amp limits double with two batteries in parallel. However, I see a lot of folks assuming a single 206Ah battery is equivalent to two 100Ah. That is not the case. To power a typical 2000W inverter, you need at least two of these batteries, either two 100Ah or two 206Ah. The 206Ah gives you twice the storage capacity, but not twice the amp delivery rate. Storage capacity is still an important feature. I bought two of the 206Ah batteries to help ease recharge anxiety. So far, I like them a lot.

A couple things not clear in the spec sheets:

Under Balancing Voltage it says <14.4V. I found that odd given many BMS balancing systems only begin to balance at about that voltage. I asked the question on the SOK FB group and got an answer from the SOK rep. They said the SOK BMS does continuous balancing up to 14.4V. Apparently it's a real thing, but I don't know how it compares qualitatively to other balancing systems.

Although not listed in the spec sheets, the SOK rep also told me the BMS over-current cut-off is 130A. That's well above the recommended operational max of 100A. They said the 100A value was intentionally conservative. You should still use 100A for sizing your system and in daily use. It's just good to know there is some wiggle room in case you accidentally over shoot at times.
I might be mixing up terminology, but the BMS Discharge cutoff according to your pdf spec sheet says 330a at I think 16 ms,.... it also lists a max of 200a for 3 seconds and then the other 100a limit you mentioned. I also saw on the FB the SOK rep mention 130a. If I was to guess, and only a guess, I'd imagine 100a is the recommended "conservative" top end discharge for extended use. 130a is a more "liberal" top end for daily use, but not recommended. 200a is for 3 second surges. And 330a is drop dead limit, pull the plug limit. Again, guessing. Yours is as good as mine. Luckily I dont plan to go anywhere near 100a.
 
When I first got my two 206Ah SOKs I ended up putting them in parallel and charged them using a Victron Blue Smart IP67 charger which does 12V @ 17A. This was to get them to the same SOC in preparation for putting the batteries in series. It took about 12 hours but I only had to do it once.

Now they get charged using a Victron Inverter/Charger which is setup to charge them at 40A. If I start charging when the batteries are down to roughly 30% SOC it takes something like 5 maybe 6 hours (not sure exactly) to charge the two in series. Soon I'll also be charging via solar.
Hello @rmaddy. I have a 12V 100AH SOK battery and a Victron Blue Smart IP65 charger (15A). What did you set the absorption voltage and float voltage at when when charging? Did you create a Custom setting to use the SOK recommended charge voltage of 14.6V (both absorption and float?) or just used the standard Li-ion setting? Thanks!
 
I think I used 14.3V or 14.4V absorption and 13.6V or 13.5V float. 14.6V absorption should be OK but 14.6V float would be too high. The SOK data sheet makes no mention of a good float voltage.

Using the Lithium defaults of the charger should be a good starting point at least. Then optionally tweak the absorption. I'd also lower the float time to 15 minutes if possible, 1 hour otherwise.
 
I think I used 14.3V or 14.4V absorption and 13.6V or 13.5V float. 14.6V absorption should be OK but 14.6V float would be too high. The SOK data sheet makes no mention of a good float voltage.

Using the Lithium defaults of the charger should be a good starting point at least. Then optionally tweak the absorption. I'd also lower the float time to 15 minutes if possible, 1 hour otherwise.
@rmaddy thank you for the quick reply. I have the absorption at 14.6V and the default for the float is 13.8V. Is 13.8V to high or should I manually set it to 13.6V? I noticed the data sheet didn't have a recommendation; adds to my confusion. To make the custom settings I enabled "advanced settings," then selected "user defined" presets and adjusted the absorption to 14.6V and left the float at 13.8V. I did not see the ability to adjust the float time, even after selecting the "Expert mode" option. I could set a time limit for Bulk and Absorption. Thanks!
 
The Lithium defaults are probably fine. Assuming you are only doing this once with the charger to get the batteries at the same SOC, the exact charge numbers aren't super critical. Once you get the batteries charged together in parallel and you get them hooked up into your system, then getting your other charge sources setup is more important.

If using this charger is your only means of regular battery charging then that's a different story.
 
@rmaddy I only have the single 12V 100AH SOK for now; I purchased a second one but it will not be here until end of Sep. In the interim I'm using this single SOK to add capacity to a Goal Zero Sherpa 100AC for camping (via the 12V 10A car charger input). So I will recharge it a few times before I balance it with my second one to use on a 24V system. I plan to purchase a Growatt 3kW 24V 150VDC 80A Off-Grid Inverter in the next two weeks. I'm new to all of this and learning as I go/have time. Thanks for the support.
 
Hi All, I’m a newbie and I just finished installing solar system. I went with Renogy and so far i’a happy with it. I also bought A Simarine Pico + monitoring system that I’m ready to install. Tried to talk with SOK with no help, in fact I asked the person about C ratings for my SOK 206 and he had no clue what that was. Can anyone help, I need the info for programming the system . C-5,C-10 and C-20.
Thanks, Ron
 
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