New Battery on Amazon and Ebay - Global Power 12V100AH LIFEPO4 - $399! Has anybody actually bought one yet? Torn it down yet?
- Thread starter Indepthdude
- Start date
Thanks! Might be too fancy for my use
I do have a Giandel inverter but I'm mainly intending on using the batteries to add capacity to my portable power stations in grid outages. So I should be charging very infrequently. And I'd like to charge quickly from a generator at that time.So far Global Power hasn't responded to my message on eBay asking about the BMS shutting down charging at 13.8, so I might have to switch plans and go to a different battery.
Bogus answer huh? "Save some capacity left in the battery"? Uh, no. It's a CYA statement cuz it's hitting over-voltage before the pack gets to full voltage/charge. And battery charging isn't 'close enough', it's when the cells are full. SMH
At 13.8V the pack is fully charged - 3.45Vpc. Anything over that is going to just bleed off right away anyway. Full charge voltage should be measure an hour after charging termination - when the pack settles to it's resting state/voltage.
It's a good charge setting if your bms constantly shuts off early. If the bms does any balancing then it's been recommended to 'absorb' them there after the battery reaches that voltage, at a rate of 10 minutes per 100AH. Some batteries will charge all the way to 14.2-14.4, even 14.6/3.65Vpc, but it's not unusual for them to shut off earlier.
The way to gain confidence is to charge the battery fully, to 13.8V, or whatever you can get to without the bms shutting down, and then do a capacity test till it shuts down at under voltage, measure how many amps you get out of it. You can use a smart shunt, clamp meter, or just a known amperage device and time it. Then you'll know if it's putting out it's full 100Ah of energy. If it's not then you have grounds for a return or replacement request. This should be done at 20*C/68*F.
If you're going to series connect make sure they are rated for such - some are and some are not - depends on the bms.
Investing in a programmable charger for lifepo is a worthy investment. I've spent nearly a grand on charging sources - new converter/charger, dc-to-dc charger, and a PV system with charge controller.
At 13.8V the pack is fully charged - 3.45Vpc. Anything over that is going to just bleed off right away anyway. Full charge voltage should be measure an hour after charging termination - when the pack settles to it's resting state/voltage.
It's a good charge setting if your bms constantly shuts off early. If the bms does any balancing then it's been recommended to 'absorb' them there after the battery reaches that voltage, at a rate of 10 minutes per 100AH. Some batteries will charge all the way to 14.2-14.4, even 14.6/3.65Vpc, but it's not unusual for them to shut off earlier.
The way to gain confidence is to charge the battery fully, to 13.8V, or whatever you can get to without the bms shutting down, and then do a capacity test till it shuts down at under voltage, measure how many amps you get out of it. You can use a smart shunt, clamp meter, or just a known amperage device and time it. Then you'll know if it's putting out it's full 100Ah of energy. If it's not then you have grounds for a return or replacement request. This should be done at 20*C/68*F.
If you're going to series connect make sure they are rated for such - some are and some are not - depends on the bms.
Investing in a programmable charger for lifepo is a worthy investment. I've spent nearly a grand on charging sources - new converter/charger, dc-to-dc charger, and a PV system with charge controller.
I can confirm that the 13.8 cutoff is due to poor pack balance. I added an active balance board and after properly balancing the pack the bms wouldn't cut out until 14.4-14.6. I've torture tested @12v and around 85a on a single battery and they passed with flying colors, however on a 48v system I cannot do even 1 full cycle with a 4s 2p pack at 100a w/o blowing the fet traces right off the board. I contacted Jim Gee and we reached an equitable settlement, but I would not recommend these batteries for use on anything but 12v systems.
He didn't seem familiar with this issue when I contact him. Did he refund you?
Partimewages
Solar Addict
What balancer did you add?
https://www.amazon.com/gp/product/B09KVHZFJ5 I bought them out after I saw they worked, so who knows when they'll get more. you can find then on ebay direct from china, but this was the only us source I found. they worked great 7 out of 8 times one was less than functional.
he offered a full refund if I returned the pallet, or a partial refund if I fixed the issues myself and shared my discoveries with him. I chose partial.
Thanks for sharing your experience!
I have a feeling that to smoothly run a 48v system up to 100amp discharge and full cycle will require all battery cells and modules fully consistent and synchronized.
This mean all 16 cells have same volt, same SOC, same capacity, connected with same wire length and same minimum Omhs drop in between, etc. This could be hard to achieve using multiple pre-made 12v batteries, without very thorough tuning.
But the price point is so good that I’m still tempted to buy 4 and merge to my existing BH 16 cells 48v system.
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May I ask what voltage system do you use them for and what percentage of total capacity do you discharge/charge regularly?
I was testing these for use in multiple systems. I bought a pallet of 30 batteries. I ended up completely replacing the individual bms's on 8 batteries with 1 external bms for a 48v system. If I was to start over, I would not purchase these. for a 48v system I would probably just get a server rack battery from signature solar only $300 more a better warantee and a proven track record. If I was chasing lower cost I would get 2 of signatures 24v 100ah packs and an external bms, still less labor than trying to make these work and a better price. 2x@499 and 100-150 for an external bms. I ended up using these because I had a client that needed his system up and running asap and I didn't have the time to deal with returning these and reordering from someone else.(he was spending $600 a month on propane for generators)_ As I have already posted, with an active balancer these performed fine @ 12v, but I would not trust them @24v or 48v, as I experienced multiple failures on 24 & 48v systems. the seller was accommodating vis a vis warantee, but the amount of time I lost making these work is not something I would choose to do again. I will soon be making a 4 battery pack install with 120a 4s jbd bms's installed into the individual batteries to see if a bms change will allow these to function to spec.
I got in 2 Global Power 100AH batteries this week, and both arrived at 13.4V. I charged them both with a Noco genius 10 and the charger got to 100% and both batteries settled at around 13.8V. It'll be a month or so before I'll be able to install them in the trailer and run them under load with the inverter.
Both batteries were very well packed (double boxed) and arrived safely.
Both batteries were very well packed (double boxed) and arrived safely.
FWIW I'm considering these for our Airstream trailer. On Ebay (https://www.ebay.com/str/goiptvllc?_trksid=p2047675.m3561.l2563) there is the $350 price category and there is a Marine battery at $320. I asked GP what the difference was and the owner responded promptly and said there was no difference only that Ebay charges more for the non-Marine category.
@jwasilko mentioned a $298 price, I'm curious where that came from?
@jwasilko mentioned a $298 price, I'm curious where that came from?
I just purchased a 3rd battery on 5 March for $298 and received it today. Just checked the listing and the price went up to $320.
Richard Lee
New Member
Maybe it "has a low temp shutoff"? (Saw that on Ebay listed for 320USD).