Just purchased 4 BATTERY HOOKUP 3.2V 100ah MODULES

[Kapnkaaos]

Hey guys,

New here! I have been researching for a couple months (new to solar and battery tech), and am planning a solar system for a shed/yard lighting, and was thinking about ordering 2 of the 4 packs to make a 24v battery.

For this, would I just use a Daly 8s 24v bms? What do I use to top balance?

Waiting on solar kit from Santan solar with 3 additional panels for 1500w pv in total. And reliable 3000w 24v inverter.

I'd like to keep whole setup under 2k, but like stated above, not sure how to build 24v battery with the battery hookup 4pack banks.

 

[ksmithers]

Hey guys,

New here! I have been researching for a couple months (new to solar and battery tech), and am planning a solar system for a shed/yard lighting, and was thinking about ordering 2 of the 4 packs to make a 24v battery.

For this, would I just use a Daly 8s 24v bms? What do I use to top balance?

Waiting on solar kit from Santan solar with 3 additional panels for 1500w pv in total. And reliable 3000w 24v inverter.

I'd like to keep whole setup under 2k, but like stated above, not sure how to build 24v battery with the battery hookup 4pack banks.

You would connect all packs in series (+ to -) using bolts. I think the lug holes are 5/16". I used 1/4"-20 bolts with washers just because I had a bunch on hand. The Daly 8s 24v should be the one you need (be sure it's for lifepo4 chemistry). For top balance, I connected all positves to a long buss bar & all negative to a different buss bar. Using a Riden 6006 to supply 3.65v. Any 30v constant voltage/constant current power supply would work. See my pic in a previous post in this thread.

 

[Kapnkaaos]

Thanks! This helps a lot.

Once I top balance like you mention above, that's when I would connect the 8s 24v Daly lifepo bms, right?

Additional question for anyone...I've been reading a lot about balancing cells... How do I balance these 20p packs, if they get out of balance down the road? Re do the top balance method @ksmithers describes? Does the Daly bms keep them in balance as they cycle? Apologies, if this is a silly question, just want to make sure I am on the right path.

Also, should I go Daly bms or Overkill bms with Bluetooth?

 

[ksmithers]

Thanks! This helps a lot.

Once I top balance like you mention above, that's when I would connect the 8s 24v Daly lifepo bms, right?

Additional question for anyone...I've been reading a lot about balancing cells... How do I balance these 20p packs, if they get out of balance down the road? Re do the top balance method @ksmithers describes? Does the Daly bms keep them in balance as they cycle? Apologies, if this is a silly question, just want to make sure I am on the right path.

Also, should I go Daly bms or Overkill bms with Bluetooth?

Correct. Top balance first then rearrange your pack to the desired configuration and attach BMS.

I'm definitely no expert (the bulk of my knowledge comes from Wills YouTube channel). My understanding is; because the cylindrical 20p cells within each pack is in parallel, they essentially self balance within the pack as they cycle. The main purpose of the bms is to balance each of the pack assemblies in series. So no single pack voltage should be vastly different than any other individual pack in the series.

Honestly, my packs were so close in voltage, I probably could have skipped the top balance & just let the BMS do its thing.

I bought the overkill BMS for a little piece of mind. The Daly may be great but I like the fact that Steve @ overkill really takes the time to test each & every one of his products. My 24v BMS came with a COMPLETE set of testing parameters. & he does that with everything he sells.

 

[Epfd217]

My 4 pack appeared close on initial testing, but once I started charging there were two packs that were clearly a higher SOC than the other two. First pack to hit 3.65, 2nd was at 3.58. Pack 3 was 3.48 and pack 4 was 3.44.

Rather than screw around with it, I ordered a power supply to make sure they get a proper top balance.

 

[Epfd217]

Finally received my power supply and completed the top balance yesterday. Now all four packs are resting exactly the same.

I ran my first test once I got it assembled. I used a group 31 battery box, 5/16" stainless hardware and some materials from around the house.



I used the 1/4" foam and some cardboard to pad and separate the packs. They were rubbing already without the buffer. Joining packs isn't as pretty as I'd like, but thats the difficulty of these packs. Hardware is wrapped is lots of tape for now.

I ended up mounting the BMS to a plastic box on top of the cells. Its not secured for right now, but ill figure something out. Finally, I ran some 3/8" battery post terminals through the top of the box and connected it all.

The only thing I have that can produce 20a consistently is a crock pot. I ran it through my 400 watt inverter and started the test.



6.5 hours later I had a result. Because of the heater cycling on the crock pot it was an average discharge of 17.66 amps per hour. The BMS showed 0 ah remaining and continued running for another 48 minutes. The test stopped when the inverter hit low voltage disconnect. I never actually hit the BMS low voltage.

From full to inverter disconnect, my math shows 114ah using a .175c rate.

Currently back on the charger to see how much power goes in.

 

[Epfd217]

Also, the cells remained perfectly in balance until the bottom 10%. Even then they were still only separating by .035v. Im extremely impressed. The top balance was completely necessary for my to get full potential. Before the top balance you can read above, my pack was more than .1v different between the packs.

 

[j8j]

Thanks to the contributors here for data on these cells. I'll try to add back to the group with my build experience. I ordered 16 units to make 4 each 12V 100Ah packs. I used the following materials and attached are some construction photos. Very tight fit in this box but they are working great and testing on my victron inverter charger is showing an average capacity of 108ah per pack. I'm using this in an RV with all packs in parallel to keep the 12V features working. With 4 in parallel the most I'm using is about 275Amps split 4 ways on discharge and charging at 120amps. Nothing getting even warm at those rates. Divide by 4 for the pack amps. Each battery pack weighs 33lbs fully built out. At a nominal 12.5V and 108Ah X4, I am seeing about 5KWH of capacity from the set of 4packs in my RV.

I ordered the JBD 150A from LLT, they shipped fast (12days to the West coast USA) and they work great. The only negative is that I ordered the Bluetooth adapters to monitor them and they only shipped 3 instead of 4 and now two months later they still haven't made good on that after repeated emails and promises. so I ordered one on ebay from another vendor and it works good too.

4S Lifepo4 Battery bluetooth BMS with 100A or 150Aconstant discharge current for 12V LFP battery pack - LLT POWER ELECTRONIC

1) Application:this smart BMS can work for 4S Lithium ion or Lifepo4 Battery ,client can choose based on your battery chemistry features 2) Current : constant current of this version BMS can be 100A or 150A 3) Dimension:315*120*10mm 4) Functions : has full sets of protection for Li ion or...

www.lithiumbatterypcb.com

Used this Milwaukee organizer as the case. Toss the bins and cut out the divider that runs across the box with a utility knife. install the Anderson connector in the front right corner with a knife and some nuts and bolts.

Milwaukee 10-Compartment Red Deep Pro Portable Tool Box with Storage and Organization Bins for Small Parts 223875 - The Home Depot

The Milwaukee Jobsite organizer is the most versatile of its kind and was designed for increased productivity and up to 20% more capacity than the competition. Designed with the needs of the professional

www.homedepot.com

I used the following wire and connectors. I used hydraulic crimpers for the connectors. 2ea 6awg compressed in one Anderson 1/0 pin work well. All 6AWG in the battery box. Anderson (copy) 175 connectors to make the connecting easy and safe for me (no exposed lugs).

https://smile.amazon.com/gp/product/B0161Z7WZI

https://smile.amazon.com/gp/product/B073FF585N

https://smile.amazon.com/gp/product/B08FY7X93J

I used 5/16-18 x 1/2 grade 5 bolts with nylock bolts to connect the packs and BMS. Covered the battery lugs with fabric padded tape and then vinyl 3M tape to insulate.

Once it all tested I put 0.31 mil poly film in the cracks between the batteries and the case etc., pressed it down in the cracks and sprayed in Great Stuff expanding foam and let it cure. Then cut the foam level with the tops of the batteries. Not pictured I then installed a layer of 0.060 ABS plastic sheeting over the batteries routing the BMS wires and notching for the 6AWG power leads to the BMS and Anderson connector.

https://smile.amazon.com/gp/product/B08R9W4NZW

GREAT STUFF 12 oz. Gaps and Cracks Insulating Spray Foam Sealant 227112 - The Home Depot

GREAT STUFF Gaps and Cracks is a polyurethane-based insulating foam sealant that fills, air-seals and insulates small gaps (up to 1 in.) inside or out. But you probably guessed as much from the name. What you might not have guessed is how easy it is to use (thanks to the straw applicator) or how...

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HDX 12 ft. W x 400 ft. L 0.31 mil High Density Painters Plastic Sheeting HSHD12-400 - The Home Depot

Keep paint spills and drips off the floor with the HDX 12 ft. x 400 ft. 0.31 mil High-Density Plastic Painters Sheeting. It is made using high-density clear polyethylene for reliable protection and unobstructed

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Scotch 1 in. x 11.1 yds. Permanent Double Sided Extreme Mounting Tape 414-LONGDC - The Home Depot

For your toughest jobs, go for our strongest hold-Scotch Extremely Strong Mounting Tape. Equipped with our powerful permanent adhesive, this double sided tape defies gravity, holding an item up to 20 pounds. It's weather resistant for a long lasting bond, indoors and outdoors. So whether you're...

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I used some of the 0.060 ABS sheet heated and bent to make some holders for the BMS and used double stick tape to hold it in place. I used some of the shipping foam from the batteries to complete the padding between the ABS and the lid of the Milwaukee box.

 

[quili]

I'm assembling a 48v 200ah battery with 32 packs of these. hopefully I can share my experience after I finish the assembly.

Here are some pics on how potentially would look after I finish the project.

 

[ksmithers]

Finally received my power supply and completed the top balance yesterday. Now all four packs are resting exactly the same.

I ran my first test once I got it assembled. I used a group 31 battery box, 5/16" stainless hardware and some materials from around the house.

View attachment 53955

I used the 1/4" foam and some cardboard to pad and separate the packs. They were rubbing already without the buffer. Joining packs isn't as pretty as I'd like, but thats the difficulty of these packs. Hardware is wrapped is lots of tape for now.

I ended up mounting the BMS to a plastic box on top of the cells. Its not secured for right now, but ill figure something out. Finally, I ran some 3/8" battery post terminals through the top of the box and connected it all.

The only thing I have that can produce 20a consistently is a crock pot. I ran it through my 400 watt inverter and started the test.

View attachment 53956

6.5 hours later I had a result. Because of the heater cycling on the crock pot it was an average discharge of 17.66 amps per hour. The BMS showed 0 ah remaining and continued running for another 48 minutes. The test stopped when the inverter hit low voltage disconnect. I never actually hit the BMS low voltage.

From full to inverter disconnect, my math shows 114ah using a .175c rate.

Currently back on the charger to see how much power goes in.

What were your BMS settings? I set mine per the instructions but I think it is cutting off early due to one of my cells being high.

 

[Epfd217]

What were your BMS settings? I set mine per the instructions but I think it is cutting off early due to one of my cells being high.

@ksmithers I am using the Overkill Solar bms and used his settings. I haven't changed anything.

My discharge test shutoff because my inverter hit low voltage disconnect before the BMS did.

 

[Desyth150]

@Epfd217 Thanks for the pics showing how you crammed the batteries into the box. I'm looking to do pretty much the same thing.

It looks like you just bent back the leads from each back to line them up on edge. Did you consider snipping out some of the black plastic sheathing to reduce any rubbing or pressure on the leads?

What did you use to connect the packs together? I'm planning on some short nuts and bolts and then taping them up like you did.

 

[Epfd217]

@Epfd217 Thanks for the pics showing how you crammed the batteries into the box. I'm looking to do pretty much the same thing.

It looks like you just bent back the leads from each back to line them up on edge. Did you consider snipping out some of the black plastic sheathing to reduce any rubbing or pressure on the leads?

What did you use to connect the packs together? I'm planning on some short nuts and bolts and then taping them up like you did.

I didn't bend anything to make them fit. I did need to trim a tiny bit of heat shrink on the actual leads, but they mount to each other flat without any interference. I used the shortest 5/16" bolts I could find. Nut, bolt and washers.

I made it so the two terminals and the balance lead all had wires trailing out the bottom. It made it easy to tape up. Nothing is pulling on the battery leads or the balance leads.

 

[LVLAaron]

Finally got my batteries & Power supply figured out. The battery packaging from BatteryHookup.com left a little to be desired. There were 2 boxes of 8 packs. There was one side of each box that had no padding. The packs were fine but I believe they could have been better protected. They were definitely NOT packed as pictured on the website. (8th cell pack was very well packed within its own box atop the other cells)

I am currently top balancing these cells. I put together a Riden 6006 60v 6A supply for the task. This sucker gets hot! At 60v-6A it clocked over 120°F & climbing. I ducted the switching power supply fan to the case cooling sots with a cut up beer can & 3M aluminum tape. It consistently stays around 100°F now. I may add an intake fan or reconfigure the existing fan in the future if needed.

I have the exact same setup on my bench right now! 16 all tied together with probably the same aluminum bar from home depot. WIll be top balancing this week.

 

[quili]

I'm assembling a 48v 200ah battery with 32 packs of these. hopefully I can share my experience after I finish the assembly.

Here are some pics on how potentially would look after I finish the project.

here is the battery already hooked up and bms on. it's charging right now with the bms hooked up until all the batteries hit 3.6v. after charging I will finish dressing up the bms cables and install the rest of the heat shrink on all connections. thanks for watching!

 

[tlag95]

here is the battery already hooked up and bms on. it's charging right now with the bms hooked up until all the batteries hit 3.6v. after charging I will finish dressing up the bms cables and install the rest of the heat shrink on all connections. thanks for watching!

@quili That's a nice lookin' mini-DIY powerwall you're building! I'm curious on the specs or brand/model number of the enclosure you are using? I may try something very similar myself. Anyways, thanks for sharing and hope you keep us updated as you finish everything out and let us know how it's running!

 

[quili]

@quili That's a nice lookin' mini-DIY powerwall you're building! I'm curious on the specs or brand/model number of the enclosure you are using? I may try something very similar myself. Anyways, thanks for sharing and hope you keep us updated as you finish everything out and let us know how it's running!

I will find out the brand and model of the enclosure tomorrow once i get to where i have the project and share it with you. I really cant remember the brand from the top of my head.

 

[dfinn]

I've got a set of these cells on order and they will hopefully ship soon. I'll be using a 150A JBD BMS from Current Connected. This will be my first battery build, looking forward to it. These will be used in a camper in the back of my truck that I'm currently building. From the little bit that I've read it seems like cylindrical cells are a better choice for something like that that will be vibrating and bouncing around? It's also a perk that you don't have to deal with any sort of compression for these and of course the price was nice too.

 

[quili]

I will find out the brand and model of the enclosure tomorrow once i get to where i have the project and share it with you. I really cant remember the brand from the top of my head.

The Enclosure is a Technomatic Corp. E238294 32"x24"x10"

 

[tlag95]

Thanks @quili!! That enclosure looks to be a rare bird, by way of the Google-sphere anyway...but those dimensions really help! Thanks for taking the time to track that down!