Batteryhookup 8ah headway cells capacity not 95% as advertised.

[nebulight]

Just a heads up these are advertised at 95% capacity and after testing 2 of the these cells, I'm seeing closer to 67% capacity. Now I'm only discharging to 2.8v, but I think going to 2.0v with lifepo4 is too low and probably wouldn't yield that much more. My test:

Charge to 3.65v at 4 amps and absorb until 2amp charge rate
Wait 5 min
Discharge to 2.8v
Wait 5 min
Charge to 3.65v at 4 amps and absorb until 2 amp charge rate

For the price ($5 per cell), I'm not that upset as I'm just going to use these for temp cells while hooking up 12v loads and prep for my camper van build. However I just thought I'd post for those that are looking to build larger packs with these cells.

Cell 1:



Cell 2:

 

[sunshine_eggo]

You really should go to 2.5. If the cells are safe to use, it won't hurt them. If it hurts them, you don't want to use them.

I would be pissed.

0.67 * 8 * 3.2v / 1000 = 0.017152kWh

$5/.017152 = $291/kWh

That's about twice what new cells cost.

 

[Alkaline]

jehugarcia is the only guy cheerleading for these I saw them and thought what a rip.

 

[nebulight]

well for me, i originally bought them YEARS ago for a dump when I was capacity testing my cells with a powerlab unit. Since then I just use them when I need a 12v source for testing. I've run them down to 0v way too many times and my old set finally died. I already had busbars and cell holders for them so I just ordered another set at $5 per cell (but the $14 shipping was a killer). They are nice in a 4s config to put in a drawer when not in use. But these cells are powerful enough to jump start a car (which I've done several times).

For 1 set for a 12v bank, I'd say it's worth it to have them laying around for testing. For anything useful, I wouldn't bother.

 

[curiouscarbon]

Just a heads up these are advertised at 95% capacity and after testing 2 of the these cells, I'm seeing closer to 67% capacity. Now I'm only discharging to 2.8v, but I think going to 2.0v with lifepo4 is too low and probably wouldn't yield that much more. My test:

Charge to 3.65v at 4 amps and absorb until 2amp charge rate
Wait 5 min
Discharge to 2.8v
Wait 5 min
Charge to 3.65v at 4 amps and absorb until 2 amp charge rate

For the price ($5 per cell), I'm not that upset as I'm just going to use these for temp cells while hooking up 12v loads and prep for my camper van build. However I just thought I'd post for those that are looking to build larger packs with these cells.

Cell 1:

View attachment 121145

Cell 2:

View attachment 121146

thanks for documenting the tests

did you buy the new listing or used listing?

BH used to offer "new" HP 8Ah cells. i bought some and will try to do some tests and see what they are like. this was before they only offered used ones.

kind regards, thanks again for the screenshots and data ??

 

[nebulight]

These were the used listing.

Cell 3:

 

[meetyg]

Maybe you should try to do a proper test:
1. You should discharge until 2.5v
2. Let the cells absorb @3.65v untill the Lifepo4 standard 0.05C which would be 400mA for these 8Ah cells.

I think that cutting off at 2 amps absorption might not be fully charging them.

Let us know how it's doing...

 

[KITROBASKIN]

A few months ago I got the 24V ¨Super Beast¨ from batteryhookup. That is 48 count, not tested individually 38120 LFP high discharge cells in a housing that is very modular and easy to play with. The price is $250 and about $40 shipping (I think) to our region. This unit is described as 1.23kWh 48Ah 24V that can also be used as 12V (no BMS). Given that our place has both 24V and 12V systems, the idea of easily replacing bad cells and easily monitoring voltage for each cell, along with possible experiments with ebike capabilities, it was worth the chance for me. Now that the wonderful diysolarforum is a part of my life, prismatic cells have a lot to offer, and the distributed experience/skill on this forum is delightful, at times stunning, and much appreciated.

The purchase did not go well, with most cells behaving badly. The numerous low voltage disconnects involved with testing cells may very well have damaged (made useless) a brand new Victron Phoenix 24/1200 inverter. Gratefully, batteyhookup refunded me more than I asked for. Northern Arizona Wind And Sun in Flagstaff Arizona was understandably cautious, yet after numerous emails and phone calls trying to troubleshoot, they got Victron to replace under warranty. Now I have two SOK 12V 100Ah bluetooth batteries. The 16 Headway cells I have functioning will never cohabitate with the new Victron.

I´m wanting to make a thread, hoping to bring that broken inverter back to life; thinking the danger zone section of diysolarforum might be a good place to post?

 

[meetyg]

A few months ago I got the 24V ¨Super Beast¨ from batteryhookup. That is 48 count, not tested individually 38120 LFP high discharge cells in a housing that is very modular and easy to play with. The price is $250 and about $40 shipping (I think) to our region. This unit is described as 1.23kWh 48Ah 24V that can also be used as 12V (no BMS). Given that our place has both 24V and 12V systems, the idea of easily replacing bad cells and easily monitoring voltage for each cell, along with possible experiments with ebike capabilities, it was worth the chance for me. Now that the wonderful diysolarforum is a part of my life, prismatic cells have a lot to offer, and the distributed experience/skill on this forum is delightful, at times stunning, and much appreciated.

The purchase did not go well, with most cells behaving badly. The numerous low voltage disconnects involved with testing cells may very well have damaged (made useless) a brand new Victron Phoenix 24/1200 inverter. Gratefully, batteyhookup refunded me more than I asked for. Arizona Wind And Sun in Flagstaff Arizona was understandably cautious, yet after numerous emails and phone calls trying to troubleshoot, they got Victron to replace under warranty. Now I have two SOK 12V 100Ah bluetooth batteries. The 16 Headway cells I have functioning will never cohabitate with the new Victron.

I´m wanting to make a thread, hoping to bring that broken inverter back to life; thinking the danger zone section of diysolarforum might be a good place to post?View attachment 121282

Did you top balance the cells before use?
Maybe an imbalance was the cause of those many LV disconnects.

 

[sunshine_eggo]

A few months ago I got the 24V ¨Super Beast¨ from batteryhookup. That is 48 count, not tested individually 38120 LFP high discharge cells in a housing that is very modular and easy to play with. The price is $250 and about $40 shipping (I think) to our region. This unit is described as 1.23kWh 48Ah 24V that can also be used as 12V (no BMS). Given that our place has both 24V and 12V systems, the idea of easily replacing bad cells and easily monitoring voltage for each cell, along with possible experiments with ebike capabilities, it was worth the chance for me. Now that the wonderful diysolarforum is a part of my life, prismatic cells have a lot to offer, and the distributed experience/skill on this forum is delightful, at times stunning, and much appreciated.

The purchase did not go well, with most cells behaving badly. The numerous low voltage disconnects involved with testing cells may very well have damaged (made useless) a brand new Victron Phoenix 24/1200 inverter. Gratefully, batteyhookup refunded me more than I asked for. Arizona Wind And Sun in Flagstaff Arizona was understandably cautious, yet after numerous emails and phone calls trying to troubleshoot, they got Victron to replace under warranty. Now I have two SOK 12V 100Ah bluetooth batteries. The 16 Headway cells I have functioning will never cohabitate with the new Victron.

I´m wanting to make a thread, hoping to bring that broken inverter back to life; thinking the danger zone section of diysolarforum might be a good place to post?View attachment 121282

I see 8 cells in series without BMS protection.

You asked for everything that went wrong, and you don't deserve warranty.

 

[MisterSandals]

after testing 2 of the these cells, I'm seeing closer to 67% capacity.

It looks like you are discharging these 5Ah cells at 4A (.8C).
I believe most cells are rated at .2C.

Discharging at 4x the rate that they are rated at could explain some of your "lower than expected" capacities.

 

[KITROBASKIN]

I explained everything I could remember to both Battery Hookup and Northern Arizona Wind and Sun, including many images including the one here. I never said I was an expert in any way. I did not know about diysolar and did not get instructions from batteryhookup that all cells needed to be charged fully individually or only in parallel. Initial voltage check looked good (8S 6P) and after first charge, every battery was good. Parallel sets started to go down with light use. That is when I separated all of them and began charging 8 at a time that had the closest voltage. This began the process of finding out which batteries were unruly. I am learning, I have fuses and breakers. Note the conductive tools nearby. I should have posted this in the danger zone but wanted to add information about Headway here. Batteryhookup.com is legit in my book. He told me they sell a bunch of these packs.

Just wondering if some people get uptight hearing about a Victron issue. The inverter only flashed alternating green and red LEDs like it did with LVD, but no energy. I hoped that some kind of firmware update could reset the LVD from being stuck, but Northern Arizona said no. Phoenix inverters are fairly straightforward, or something like that..

 

[KITROBASKIN]

Can I show you backcountry battery management system? (Danger, not for home use). You get the battery with the high voltage, then with a downward strike, brush but don’t linger…

 

[MisterSandals]

You get the battery with the high voltage, then with a downward strike, brush but don’t linger…

I'm gonna need a video. Fire starter? What's the black box in the shadow under your hand?

 

[meetyg]

Can I show you backcountry battery management system? (Danger, not for home use). You get the battery with the high voltage, then with a downward strike, brush but don’t linger…
View attachment 121316

Are you serious?

 

[KITROBASKIN]

I'm gonna need a video. Fire starter? What's the black box in the shadow under your hand?

I wore a headlamp for the photo, the black area is shadow.
The 16 remaining batteries that function are connected 4 series, 4 parallel in the truncated “Beast” 12 Volt configuration (Caution again advised as the structural throughbolts are too long, so the unit is held together by the positive and negative connections. Don’t be doing a jostle with it). I had that bad cell on hand (only ~1V) so used it for the image. I would have to remove a cell from the pack to show the spark. I will do it if my credibility is on the line.

Please understand the connecting clamps, relatively thin wire, splayed strands on the business end of the wire, and the alloy coated structural screw is somewhat loosely wrapped with the copper wire. These all combine to keep the connection less grabby. The head of the screw is on the hard surface, providing something of a fulcrum while one strikes downward with alacrity. Should a Spark Sprite initiate mischief anyways, the non combustible surface and proximity to an open door will allow a cool head to make a great egress.

I think I had four cells that would stubbornly stay higher than the other cells. It took about 15 to 30 strikes to lower them about a volt, if I remember correctly.

Rated at 200 Amps, these cells are to be respected, as Battery Hookup emphasizes in their ad copy. They will bite.

Pardon the dog hair.

 

[nebulight]

Maybe you should try to do a proper test:
1. You should discharge until 2.5v
2. Let the cells absorb @3.65v untill the Lifepo4 standard 0.05C which would be 400mA for these 8Ah cells.

I think that cutting off at 2 amps absorption might not be fully charging them.

Let us know how it's doing...

I've done just that. Here is Cell 4 at my first test, then at your suggestion of 2.5v discharge and recharge to 3.65 with absorption until 400mA. Not much to be had by doing this as I went from 5.039ah to 5.382ah for a 6.3% increase.



Cell 4 with 2.5v discharge and 400ma absorption:

It looks like you are discharging these 5Ah cells at 4A (.8C).
I believe most cells are rated at .2C.

Discharging at 4x the rate that they are rated at could explain some of your "lower than expected" capacities.

These are supposed to be 8ah cells so my 4amp discharge/charge test was .5c. However these cells are supposed to be able to charge 10C and discharge at 25C according to their spec sheet. https://www.evlithium.com/Headway_Battery/898.html

Bottom line, these are HEAVILY used cells and proceed with caution if you want to build a bank out of these (not sure why you would except for really unique needs). I bought a used set about 5-6 years ago and they came in at around 7-7.5ah each. When I bought this batch last week, as you can see from my tests, they are testing WELL below that now.

This is just an FYI post and NOT a bashing post for battery hookup. They can't test each of these cells then sell them for $5 per cell. Just know what you are buying.

 

[meetyg]

I've done just that. Here is Cell 4 at my first test, then at your suggestion of 2.5v discharge and recharge to 3.65 with absorption until 400mA. Not much to be had by doing this as I went from 5.039ah to 5.382ah for a 6.3% increase.

View attachment 121423

Cell 4 with 2.5v discharge and 400ma absorption:

View attachment 121424



These are supposed to be 8ah cells so my 4amp discharge/charge test was .5c. However these cells are supposed to be able to charge 10C and discharge at 25C according to their spec sheet. https://www.evlithium.com/Headway_Battery/898.html

Bottom line, these are HEAVILY used cells and proceed with caution if you want to build a bank out of these (not sure why you would except for really unique needs). I bought a used set about 5-6 years ago and they came in at around 7-7.5ah each. When I bought this batch last week, as you can see from my tests, they are testing WELL below that now.

This is just an FYI post and NOT a bashing post for battery hookup. They can't test each of these cells then sell them for $5 per cell. Just know what you are buying.

Thanks for redoing your test!
It seems like your initial experience was true.

Thanks for the "head-up"...