LiFePo Budget Battery Recommendation

[Ceefiveceefive]

Greetings!

What is Will's current LiFePo battery recommendation for folks on a budget?

 

[Dzl]

Greetings!

What is Will's current LiFePo battery recommendation for folks on a budget?

Cheapest will be building your own if you are comfortable with that, and willing to put the time and research in to learn what you need to do to protect your investment.

Beyond that, I know that the costco deal can be good when it comes around (Lion energy for $700 or $750 I think?), there are a bunch of other cheaper lifepo4 around 100Ah, not sure what is recommended. I suppose the best way to check what budget options Will specifically recommends is checking his website and latest videos.

 

[Ceefiveceefive]

Cheapest will be building your own if you are comfortable with that, and willing to put the time and research in to learn what you need to do to protect your investment.

Beyond that, I know that the costco deal can be good when it comes around (Lion energy for $700 or $750 I think?), there are a bunch of other cheaper lifepo4 around 100Ah, not sure what is recommended. I suppose the best way to check what budget options Will specifically recommends is checking his website and latest videos.

Thank you! I will be building my own at a later date. I am just looking for plug&play right now & do not want to shell out a grand for Battleborns.

I know he has recommended some in the past but have not kept up lately for changes, hence my query to you all!

 

[Dzl]

Thank you! I will be building my own at a later date. I am just looking for plug&play right now & do not want to shell out a grand for Battleborns.

I know he has recommended some in the past but have not kept up lately for changes, hence my query to you all!

Would be a cool idea for people in the know, regarding drop-in lithium batteries to keep a running thread with the latest community recommended deals, maybe there is already a thread like that started. Not something I've looked into.

 

[svetz]

Would be a cool idea for people in the know, regarding drop-in lithium batteries to keep a running thread with the latest community recommended deals, maybe there is already a thread like that started. Not something I've looked into.

I believe @Will Prowse keeps the DIY Blueprints section updated with the "safest" deals that he recommends.

 

[dmholmes]

I went through this recently. I narrowed it down to:

• SOK
• MillerTech

 

[Kish]

Would not recommend that SOK.

1. Recommended Charge Current 20 A. Your solar array will produce more than 20A on a daily basis, unless you have a tiny < 300W system. By daily charging above 20A, you'll be degrading the battery (or destroying the BMS. Not sure which of the two is the limitation for the 20A here).
2. BMS Discharge Cut-off Voltage >8.0 V. That's way, way too low for LiFEPO4 chemistry. You don't want to go lower than 10.50V (2.50V per cell). If you don't have your own external battery disconnect, then you've just bricked your battery.
3. BMS Discharge Cut-off Current 320A~340A. And finally... lol wtf? That's 70% higher than the peak current (200A). If you sized the wires in your system for 200A (or god forbid for the 100A continous rating), you'll soon have a burned wires/system, or burned down house.

As an aside:
4. BMS Low Temperature Cut-off 23°F. Why even bother have a low temp cutoff in the BMS if it's over 32F (0C?). You should never charge LiFEPO4 lower than 32F (0C), or else you will brick it. While you can technically discharge a LiFEPO4 below 0C, it's not recommended.
Discharge Temperature -22°F ~ 140°F
Charge Temperature 32°F ~ 140°F
So assuming you have that 23F BMS cutoff, it's "too high" to allow for the lowest discharge temp (-22F), and too low for the lowest charge temp (32F). It's the worst of both worlds, exactly what is it trying to satisfy?

 

[Bigbillsd]

I found the Renogy 170AH batteries to be a very good deal over last years Black Friday weekend. Around $1000 for 170ah. I could have built my own, but decided I just didn't know enough to feel comfortable enough to go that way. I have enough other bleeding edge things to deal with. So I purchased 4 of them. Its been about 10 months of using them in my 40' RV and they are the wonderful. Cannot believe i kept the LA battery's so long.
I also choose the Renogy 170's for their size factor. I could only fit 500ah of BB batteries in my space, and was able to squeeze in almot 700ah in my battery compartement instead. And saving $3000.00 dollars and getting close to 2 extra BB equivalent in AH size for that much less has me smiling many months later. Will they last as long as the BB's, who knows. Maybe, Maybe not.

 

[David Smelser]

I recently purchased two SOK 100 Ah batteries...haven't fully tested the battery, but the capacity test appears to be good (1300 watts each on initial test). I haven't conducted a full Current Load test to see how hard I can pull amps out. Charging seems to be good with 40amps going in, but I'm using an EPEVER 40A, and the SOK recommends 50A charging. I just received a 50A/60A charge controller today, and will test tomorrow on the SOKs. I believe Amazon just raised the price to $640, so going to the SOK site or eBay is probably the best price. SOK I believe will not charge tax (depending on where it is delivered). I'm not saying that these batteries will beat others, just letting folks know what I'm doing, and will let you know if I run into issues. So far no issues. I doubt I'll do a teardown (for now) since these are perfectly good LiFePo4. I've seen the YouTube teardown review, and am satisfied with the construction and configuration. I also have seen a YouTuber change two old SLAs for two SOKs, and the SOKs seem to be operating sufficiently.

 

[Forbisher]

Jeeez
You made like 5 almost identical posts about SOK batteries spamming the forum today.
How much are they paying you???

I recently purchased two SOK 100 Ah batteries...haven't fully tested the battery, but the capacity test appears to be good (1300 watts each on initial test). I haven't conducted a full Current Load test to see how hard I can pull amps out. Charging seems to be good with 40amps going in, but I'm using an EPEVER 40A, and the SOK recommends 50A charging. I just received a 50A/60A charge controller today, and will test tomorrow on the SOKs. I believe Amazon just raised the price to $640, so going to the SOK site or eBay is probably the best price. SOK I believe will not charge tax (depending on where it is delivered). I'm not saying that these batteries will beat others, just letting folks know what I'm doing, and will let you know if I run into issues. So far no issues. I doubt I'll do a teardown (for now) since these are perfectly good LiFePo4. I've seen the YouTube teardown review, and am satisfied with the construction and configuration. I also have seen a YouTuber change two old SLAs for two SOKs, and the SOKs seem to be operating sufficiently.

 

[Bigbillsd]

My question is: How did they make them 12.6v? Its painted on the side of the battery in one of the pictures?

 

[David Smelser]

Jeeez
You made like 5 almost identical posts about SOK batteries spamming the forum today.
How much are they paying you???

Just replying to each Thread...not entirely sure how this forum works, but give me enough time I'll figure it out. Also, I can assure you nobody is paying me any fees, not sure how that stuff works. Also, SOK wasn't my first round of trials, I went with RockPal and Miady (see pics) prior to SOK. The Miady batteries are being built to provide portable low-cost power. I can assure you Miady (or Amazon) isn't paying me to build these battery packs with cases from Harbor Freight (<$12 with a 20% off coupon in August). Basically, I've spent hundreds of my money searching for the proper solar/battery fit/solution. I'm building a shed and want to power it with solar. I'm a smalltime solar nut with a bigtime passion, and the resources to do it...so I don't need anyone's money. Also, FYI, that 50A/60A charge controller, I mentioned earlier, is being returned (see pic) back to Amazon. Not that it doesn't work, but it is too noisy (fan) for my needs. I prefer the EPEVER 40, and will probably order the 60A version Commander (Renogy).

If you're interested in discussing SOK technicals (plus other engineering interests), and how they operating feel free to reach out. I've setup a "lab" for POC to test out different solutions, and to learn about solar (and batteries). Sorry to inundate the forum with "spam"...I thought I was responding to individual threads. Was not my intention to be perceived as advertising for a fee...I can assure you, if I find something I don't like about SOK (or any other product), this forum will be the first to know.

Questions, feel free to ask.

Thanks,
David

 

[David Smelser]

@MBR

Additional pics, apparently I can only upload 10 pics at a time.

See that blue box? I can't figure out the manufacture/brand, and think it is a generic CC. It isn't bad, but very noisy. I was able to get 45.5As with my current solar panels. I only have three Q cells, with the fourth one still not deployed. I choose to build my own combiner box, which is a WIP.

Questions, please ask.
David

 

[David Smelser]

My question is: How did they make them 12.6v? Its painted on the side of the battery in one of the pictures?

I believe it is 12.8v...I can see how 12.8v can be viewed as 12.6....attached is a closer view of the batteries.

 

[Bigbillsd]

Looks kind of suspect to me. Did they really misspell their email address on the battery? www.sokbattery.com vs sales@sokbatery.com Notice the missing "T" The certificate is only good for a total of 3 months. The only time I have seen that prior was on scam sites. (I was a PKI admin for a large multinational) The misspelling on the battery itself would keep me at arms length though. Are they using bad cells to get 12.8v instead of 13.6 with most LIFEPO4 batts?

 

[Dzl]

Looks kind of suspect to me. Did they really misspell their email address on the battery? www.sokbattery.com vs sales@sokbatery.com Notice the missing "T" The certificate is only good for a total of 3 months. The only time I have seen that prior was on scam sites. (I was a PKI admin for a large multinational) The misspelling on the battery itself would keep me at arms length though.

Are they using bad cells to get 12.8v instead of 13.6 with most LIFEPO4 batts?

While your other concerns are legit, this last one is not. Lifepo4 cells are 3.2V nominal, 3.2v x 4 =12.8v, referring to a 4 cell ('12v') Lifepo4 battery as 12.8v is quite common (for instance Victron labels their batteries the same way)

 

[Bigbillsd]

While your other concerns are legit, this last one is not. Lifepo4 cells are 3.2V nominal, 3.2v x 4 =12.8v, referring to a 4 cell ('12v') Lifepo4 battery as 12.8v is quite common (for instance Victron labels their batteries the same way)

Ah, good to know, my batts are fully charged around 13.6 so I would under the assumption that 3.4v was the nominal voltage. Thanks for letting me know.

 

[Forbisher]

I believe it is 12.8v...I can see how 12.8v can be viewed as 12.6....attached is a closer view of the batteries.

12V 100Ah LFP $460 plus tax lowest price leader.

Amazon.com

 

[David Smelser]

12V 100Ah LFP $460 plus tax lowest price leader.

Amazon.com

I saw this one a couple of weeks back, and it doesn't look bad. While it is cheaper...I was hesitant to try it out. One of the drawbacks is the discharge current of 20A, which can be good for some applications...I just don't have an application for it. I'll eventually need discharge of 50A or better for my new shed. At the moment I'm looking at a KiloVault battery which has 150A max continuous discharge, with a max charge of 150A as well. Pretty versatile, but pricey.

 

[Dzl]

I saw this one a couple of weeks back, and it doesn't look bad. While it is cheaper...I was hesitant to try it out. One of the drawbacks is the discharge current of 20A, which can be good for some applications...I just don't have an application for it.

5.Max continuous charge current: 1C
6.Max continuous discharge current: 1C