SOK Marine 100Ah Internal Pictures / Teardown?

[archjeb]

Hi folks,

Curious if anyone has purchased the SOK Marine 100Ah LiFePo4 battery?
Could you post pictures of the internal BMS & Battery connections?

I know Will did a tear down on the 206Ah battery, but I have yet to see a tear down on this newer 100Ah battery. Because of space limitations, I need the dimensions of the 100Ah...

SOK Lithium Iron Phosphate 12V 100Ah Battery,Marine Grade | SOK Battery USA

In stock, ready to ship.SOK Lithium Iron Phosphate 12V 100Ah Battery,Marine Grade

www.us.sokbattery.com

Also, what is the deal with the voltages that are listed on the datasheet? It says: "4.Flexible - Works in 12, 24 or 48V configurations,or connect in Parallel for Larger Capacity."

Why is 36V missing on the voltage configuration? Seems weird that I could not wire 3 in series but 4 in series is ok?

Thanks,

-J

 

[KITROBASKIN]

You might consider consulting and if it happens, purchasing from currentconnected. I’m guessing 36V is not as common and was simply left out but talk to them about it.

While I’m not likely to open the batteries up, anything else I can answer go ahead. Not surprisingly for this time of year, good sunlight for the panels is pretty short these days, and they are on the edge of not being enough. We cast off our hand-me-down generator and will have to reduce load if too many clouds. Trying not to have any down time generating.

I have had them about 6 weeks. The Bluetooth feature continues to be a learning experience for me.

 

[archjeb]

This is for a marine application. No solar. Onboard charger to charge batteries after use. 36v Trolling motor; so replacing 3 group31 AGMs wired in series for 36v. Because of limited battery locker space, I have to use 3 separate batteries to get them to fit (one at a time to slide into the storage access); one large 36V battery will just not fit. At any rate, that is the existing configuration with the 3 AGMs that are there now.

I did look at their web page and the main splash page shows 36V - its the Datasheet that shows 48v. At any rate, its really the upper voltage which is the concern to make sure the FETs on the BMS can handle the higher voltage. Since 48V is listed...36V should be fine - just thought it was a weird discrepancy on their datasheet.

----

What I really want on the tear down is how are the cells secured? On a boat, you get a lot of pounding and vibration; and I want to make sure that things are NOT going to wiggle loose internally on the battery pack.

Are all the lugs / bus bars connected with a bolt and lock washer and then some epoxy on top of that to secure the bolt? Or are they welded or soldered in place?

Has anyone had any issues with the nut/lockwasher & epoxy coming loose or has then been pretty fool proof?

-J

 

[KITROBASKIN]

Ok, part of the process of making the Bluetooth readout accurate is discharging until the BMS trips off. I did that and opened it up. It was reading about 11V before opening. I would say the design is built for sturdiness within prudent use, not abuse. Here is a link to a crude peek inside the SOK 12V 100Ah Marine LFP battery.

New video by Kitrobaskin

photos.app.goo.gl

Seems like I should be able to take screen shots from the original video if more clarity is needed. Depending on one’s internet bandwidth, videos through Google Photos servers can be low quality. No plans to open it up again unless there is failure.

 

[archjeb]

Awesome. Thanks for doing that. So it looks like the basic construction is very similar to their larger 206Ah marine battery.
Lugs have no epoxy on them...but just lock washers. Which isn't that big of deal I guess given that you can easily take the battery cover off and service the unit.

How do you like the BMS Bluetooth interface on that battery?

I need 3 in series for 36V trolling motor on a boat. Personally, I'd like to just put a Victron SmartShunt on my future setup and not worry about the individual batteries; unless you think there is some value in having some Battery info via Bluetooth on a per battery basis?

 

[KITROBASKIN]

I have a Victron SmartShunt but removed it until both SOK Bluetooth systems are fully sorted out. At this point the app is rather awkward and my lack of experience compounds the challenge. Hopefully another member here will provide input for you. The Bluetooth seems to provide good info on one battery. The other is a work in progress. A complete discharge and full charge needs to be done twice, according to SOK (I am not there yet).

The SmartShunt has options that I do not fully understand but has a good reputation.

Having three batteries for 36V, and how the SmartShunt would do that is a question. Keeping them balanced is another.

Consider reading the Victron SmartShunt manual.

Manual - SmartShunt

www.victronenergy.com

Best,
Kitro