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Building a battery bank with the 48v Panasonic Modules from batteryhookup

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PoChop

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I bought 160 of these modules from batteryhookup.com

(https://batteryhookup.com/products/40x-panasonic-48v-13s-6-4a-299-99wh-12kwh-32)

...and I want to build a 48kWh battery bank for a 48v system. I have 2 phocos 6.5kWh anygrid inverters (plan to add more soon, and probably double my panels) and 9,520w of panels. In the listing there's a video

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where a guy connects 5 for a 1.5kWh pack, and that's also what batteryhookup recommends. My question is, can I simply follow what the person in the YT video did (add 30a Daly BMS, and 50amp Anderson connectors) except instead of the small busbar use a much bigger copper busbar? Or how would you all do it? Better yet, has anyone built a larger battery pack on here with these?
 
Bad idea, but if you must then:

You need to parallel all the packs pos and neg, you must also connect all the positive sides of each cell to the corresponding cell on the next pack. For example, each pack has a #1 cell positive, and the #1 cell pos should be connected to each of the other #1 cell positives, and so forth with #2 and #3 etc. This allows a single BMS to balance all 13 cells in each pack.

Next, you should ABSOLUTELY FORGET using that cheap piece of crap Chinese BMS. Daly has so many problems I'm surprised the forum mods haven't banned talk of them. At the very least, get a bunch of the ZEVA BMS's, or an Orion, REC, Batrium, etc. Something of quality so it it doesn't burn your home down.

I wouldn't connect more than seven to ten packs together.

Personally, I think you made a mistake. These small battery banks aren't designed to be stacked for more power. They're probably best used for e-bikes or maybe computer backup power supplies or something.

If it was me, I'd tear those packs apart and see if I couldn't figure out how to turn each pack into a single larger cell by rewiring them all in parallel.
 
MurphyGuy said:
Bad idea, but if you must then:

You need to parallel all the packs pos and neg, you must also connect all the positive sides of each cell to the corresponding cell on the next pack. For example, each pack has a #1 cell positive, and the #1 cell pos should be connected to each of the other #1 cell positives, and so forth with #2 and #3 etc. This allows a single BMS to balance all 13 cells in each pack.

Next, you should ABSOLUTELY FORGET using that cheap piece of crap Chinese BMS. Daly has so many problems I'm surprised the forum mods haven't banned talk of them. At the very least, get a bunch of the ZEVA BMS's, or an Orion, REC, Batrium, etc. Something of quality so it it doesn't burn your home down.

I wouldn't connect more than seven to ten packs together.

Personally, I think you made a mistake. These small battery banks aren't designed to be stacked for more power. They're probably best used for e-bikes or maybe computer backup power supplies or something.

If it was me, I'd tear those packs apart and see if I couldn't figure out how to turn each pack into a single larger cell by rewiring them all in parallel.
Click to expand...
Thank you for responding, and i only plan to use these hopefully for 6-12 months. I have more questions, but I'm driving right now. But I searched for each of those BMS's, some of them pretty expensive, and Zeva seems to be made in Australia. Not sure how much that would add to shipping. But, do you have a more specific cost effective recommendation?
 
I'm using a couple of ZEVA 16V3 BMS, working well so far on the DIY 48V battery pack after about 4 years. Not sure what the status of that product is regarding being in stock for immediate delivery. Instead they have posted the Eagle files, Gerber & drill files, .hex files, STL files and BOM on the ZEVA website for both the BMS and CAN based color touch screen. I haven't checked availability of parts on the BOM lately but a couple of months ago when I needed to replace both photo relays and 2 of the P channel passive balancing mosfets they were not available, had to find substitute parts with the same specs.
The reason those parts failed was totally my fault, caused by some bench top testing I was doing using one of the BMS.
 
PoChop said:
Thank you for responding, and i only plan to use these hopefully for 6-12 months. I have more questions, but I'm driving right now. But I searched for each of those BMS's, some of them pretty expensive, and Zeva seems to be made in Australia. Not sure how much that would add to shipping. But, do you have a more specific cost effective recommendation?
Click to expand...
Nope.. All the supposedly "cost effective" units are mostly garbage, with many being down right dangerous.

The best case (highest probability based on forum reading) is that they damage your battery by discharging it.. worst case is they cause it to catch on fire or the BMS catches on fire itself.

When it comes to lithium cobalt, I live by a pretty simple rule.. NEVER EVER use a BMS that passes load currents through the BMS. That kind of thing is fine for an e-bike battery or a suit case style bank you can throw out the window when it starts smoking, but for larger banks, it's just dangerous.
 
MurphyGuy said:
When it comes to lithium cobalt, I live by a pretty simple rule.. NEVER EVER use a BMS that passes load currents through the BMS. That kind of thing is fine for an e-bike battery or a suit case style bank you can throw out the window when it starts smoking, but for larger banks, it's just dangerous.
Click to expand...
Amen to that, I agree and would add the same precaution for ANY battery if the current is going to be higher than 50 to 75A. Really like using a big beefy 400A contactor. To eliminate the parasitic contactor coil load I've started using a magnetic latching contactor.
 
MurphyGuy said:
Nope.. All the supposedly "cost effective" units are mostly garbage, with many being down right dangerous.

The best case (highest probability based on forum reading) is that they damage your battery by discharging it.. worst case is they cause it to catch on fire or the BMS catches on fire itself.

When it comes to lithium cobalt, I live by a pretty simple rule.. NEVER EVER use a BMS that passes load currents through the BMS. That kind of thing is fine for an e-bike battery or a suit case style bank you can throw out the window when it starts smoking, but for larger banks, it's just dangerous.
Click to expand...
The cells are li-ion, so does that change anything.
 
Li-ion is a general, catch all term for high energy density, high voltage cells (3.7V nom), of which there are several chemistry variants. A couple of common types are LCO and NMC. These are the cells you hear about in the news when an EV catches fire because they are subject to thermal "run away".
Caution is advised when using this type of cell.
On the flip side, if your battery pack is large compared to the Inverter and loads that are being powered then the discharge C rate will be low thus there will not be as much heat generated. This would also be somewhat dependent on room temperature and air circulation around the cells.
 
BentleyJ said:
Li-ion is a general, catch all term for high energy density, high voltage cells (3.7V nom), of which there are several chemistry variants. A couple of common types are LCO and NMC. These are the cells you hear about in the news when an EV catches fire because they are subject to thermal "run away".
Caution is advised when using this type of cell.
On the flip side, if your battery pack is large compared to the Inverter and loads that are being powered then the discharge C rate will be low thus there will not be as much heat generated. This would also be somewhat dependent on room temperature and air circulation around the cells.
Click to expand...
Forgive my ignorance, I'm still learning. I am wondering though, the modules do have a BMU that apparently has active balancing. Would that help, especially if I have to use some cheap Daly's. idk if I can't really afford the expense of other options, unless I can remove the cells all 2,080 of them and reconfigure them so I don't have to use so many BMS's? Also, my inverters are 2 6.5kWh phocos anygrid inverters, and the largest load I would probably run is a air compressor, freezers, washer and dryer, maybe down the road some bigger shop tools. My electric usage is pretty low, I only went with such a big bank because I'm completely off grid.
 
If the battery packs already have a built in management system with balancing then it does make sense to exploit them as much as possible. Perhaps do some research and find out if there is some kind of communication interface available for the BMU. USB, RS485, CAN. Does the BMU have an output relay that could be used to control an external contactor?
 
BentleyJ said:
If the battery packs already have a built in management system with balancing then it does make sense to exploit them as much as possible. Perhaps do some research and find out if there is some kind of communication interface available for the BMU. USB, RS485, CAN. Does the BMU have an output relay that could be used to control an external contactor?
Click to expand...
I'll have to do more research, all I know currently is batteryhookup says it's proprietary. I'm not sure how to find out if there's anything to connect to it, or how its able to balance w/o whatever proprietary connections it used before and I'm guessing it works (although not fully, presumably, w/o whatever was attached before) simply by being "used" (for lack of a better phrase) or charged/discharged.

Edit: for the record I haven't opened the box the modules came in yet, so I need to inspect them to see if a connection port exists.
 
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I humbly suggest, considering all the issues involved… It may be wise to see if batteryhook-up would accept the modules back for a small restocking fee.
 
GVSolar said:
I humbly suggest, considering all the issues involved… It may be wise to see if batteryhook-up would accept the modules back for a small restocking fee.
Click to expand...
I don't think that's an option, I made four purchases two were auction wins, all sales final and two were from a website glitch that they originally didn't want to honor, and I kinda got into a mini spat (all cool now) w/ the owner over it, plus they combined 3 of them into one ship, saving me $800. I'll just have to figure it out. This will be temporary (maybe 1 yr solution) until I get more funds for server rack batteries.

Edit:worst case (hopefully) I'll just break them down a reconfigure them somehow.
 
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PoChop said:
I don't think that's an option, I made four purchases two were auction wins, all sales final and two were from a website glitch that they originally didn't want to honor, and I kinda got into a mini spat (all cool now) w/ the owner over it, plus they combined 3 of them into one ship, saving me $800. I'll just have to figure it out. This will be temporary (maybe 1 yr solution) until I get more funds for server rack batteries.

Edit:worst case (hopefully) I'll just break them down a reconfigure them somehow.
Click to expand...
Just curious what you ended up doing with these batteries
 
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