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BigBillSD · 01-23-2023, 06:00 AM

I put solar in my bus about 4 years ago now and was looking around for ways to test them to see how they were performing when I stumbled upon an updated version of some batteries I had seen a couple years back. The price was now $30 lower and they could now be hooked up serially too. 4S4P providing 20KWH for $5400 + cabling etc. I am not sure why anyone would purchase AGM's anymore as these are $329 on Amazon.

https://amzn.to/3XuUcQN

When I first saw these batteries a couple years back, they could only be setup in parallel, 12v only. Now they can do 48v (4 in series) which would be a real game changer for an off grid home.

-Bill

PS. Now I know what to buy if my testing says my batteries are getting weak...

wopachop · 01-23-2023, 11:41 AM

Weird so it supports up to 16 batteries total? Seems odd there is a limit. With the correct wiring i dont understand why you cant in theory hook up 100 of those batteries in parallel?

TravelSolo · 01-23-2023, 12:34 PM

Quote:

Originally Posted by wopachop

Weird so it supports up to 16 batteries total? Seems odd there is a limit. With the correct wiring i dont understand why you cant in theory hook up 100 of those batteries in parallel?

Internals, terminals and the BMS's probably can't handle it, which is fine in 99.99% of use cases.

BigBillSD · 01-23-2023, 06:04 PM

Yeah, but now it can do 48 volts. Last time I looked at them they maxed out at 12v. No serial connectivity at all.

Rob_M · 01-23-2023, 10:13 PM

What do y’all think about using three of these in a 36V golf cart?

will stevens · 01-24-2023, 06:28 AM

BigBillSD · 01-25-2023, 05:55 AM

Quote:

Originally Posted by Rob_M

What do y’all think about using three of these in a 36V golf cart?

Wired in series they should be good. You would need to consider what you are using to charge them and make sure it has a Lithium setting. -Bill

TacomaJoe · 01-25-2023, 07:09 AM

Quote:

Originally Posted by Rob_M

What do y’all think about using three of these in a 36V golf cart?

These are 100A discharge so if the golf cart needs less than that, you're good to go. Might be a surge issue getting the motor going.

wopachop · 01-26-2023, 10:34 AM

Quote:

Originally Posted by BigBillSD

Yeah, but now it can do 48 volts. Last time I looked at them they maxed out at 12v. No serial connectivity at all.

Was this just marketing though? The 12v battery does not know if its been hooked up in series. The 12v battery itself are 3 cells in series with the BMS to balance and restrict loads at certain temps.

Is the buyer using a device to program the BMS differently if its a single 12v versus two 12v in series? Or do the batteries now talk to each other? Its the charger that needs to be programed. I dont think the single 12v knows its been hooked in series. Unless im missing something the only difference will be available charge amps at a certain point along with wire size.

Can anyone correct me where im wrong? Will be in the market soon for a lithium for my trailer. Im thinking it comes down to wire size and terminal size as mentioned by a guy above. Pretend you had 50 batteries in some configuration. It would take a very powerful charger and some really thick wire to work. Im guessing this is why the battery is advertised as "up to" 16 batteries in a 48v config.

Not trying to argue. Here to learn. My first thought is that it makes no sense why the original battery the OP has cannot be hooked in series.

BigBillSD · 01-27-2023, 05:01 AM

Quote:

Originally Posted by wopachop

Was this just marketing though? The 12v battery does not know if its been hooked up in series. The 12v battery itself are 3 cells in series with the BMS to balance and restrict loads at certain temps.

Is the buyer using a device to program the BMS differently if its a single 12v versus two 12v in series? Or do the batteries now talk to each other? Its the charger that needs to be programed. I dont think the single 12v knows its been hooked in series. Unless im missing something the only difference will be available charge amps at a certain point along with wire size.

Can anyone correct me where im wrong? Will be in the market soon for a lithium for my trailer. Im thinking it comes down to wire size and terminal size as mentioned by a guy above. Pretend you had 50 batteries in some configuration. It would take a very powerful charger and some really thick wire to work. Im guessing this is why the battery is advertised as "up to" 16 batteries in a 48v config.

Not trying to argue. Here to learn. My first thought is that it makes no sense why the original battery the OP has cannot be hooked in series.

It all comes down to what the BMS is rated for. They now support 48 volts, they did not before. Also, 3 LiFePo4 cells do not give you 12v, you must use 4. -Bill

TacomaJoe · 01-27-2023, 06:33 AM

Not trying to argue. Here to learn. My first thought is that it makes no sense why the original battery the OP has cannot be hooked in series.

The BMS in the battery is the brains of the system. If there's a problem it shuts the battery down. If you have one battery and it shuts down, your lights go out and start checking things. If there are 4 of them in series making a 48V system (keeps current and wire size down) and one of the batteries shuts down, it's BMS is exposed to the 48V. If its components are rated for 12, they fry at 48.

If you need 150A so your inverter can run the microwave, you could use two batteries rated at 100A discharge in parallel. Each battery would provide 75A and be happy. Again the trouble is when one of the BMSs shuts its battery down. In this case the battery that is left now has to provide the 150A for the inverter and will be overloaded.

I like the storage capacity of these, but keep in mind that if you use a bunch making baked potatoes in the microwave, you need to replace that energy. They can take a fast charge. I can charge a dead 150Ah battery in two hours of generator time where before it took forever with my lead acid.

Rob_M · 01-30-2023, 08:49 AM

I bought 3 of these based on a golf cart test (ezgo just like mine) I watched online. With the discount for 3 and free shipping, came out to about the same price.

https://enjoybot.com/products/enjoyb...42250701406423

153stars · 04-15-2023, 07:05 PM

Will Prowse tested these they can deliver really high output.They would be great for someone using more the hybrid side of inverters to inverter genny or mooch docking. Didn't choose huge battery bank. A vast majority of owners are not building air condition capable solar systems. You would want to cable accordingly

Quote:

Originally Posted by Rob_M

I bought 3 of these based on a golf cart test (ezgo just like mine) I watched online. With the discount for 3 and free shipping, came out to about the same price.

https://enjoybot.com/products/enjoyb...42250701406423