Avoid HQST!

[crustacean]

I stupidly purchased 3 HQST 100Ah batteries from this scam of a company.

My first battery died after 6 months. No customer support. My 2nd battery died after 14 months. Technically it is not dead but 6Ah capacity at 11.9 volts is basically dead. My third battery delivers 80Ah after only 6 months of light use. RUN AWAY FROM THIS COMPANY! Seriously if you even consider buying from a company without a phone number then I can not help you! Every email to them has been unreturned.

 

[sunshine_eggo]

Are these lead acid or LFP?

 

[crustacean]

LiPo4 batteries.

 

[sunshine_eggo]

You've said your peace. Please refrain from essentially making identical posts in other threads. Cross posting is at a minimum poor forum etiquette.

That out of the way...

To give you a comparison, a Battleborn user saw his battleborn battery drop to about 50Ah of capacity simply because they never fully charged them and the cells never entered the balancing phase, so over the course of 3 years, the cells lost their charge at different rates and one or more cells had dropped to 50% when others were at 100%. After holding their battery at 14.2V+ for 1-2 weeks to allow balancing, the battery delivered > 90Ah.

This may be a major contributing factor to your experience.

"Light use" implies that you were not regularly cycling any of these batteries.

Did you regularly charge your batteries to 14.4V and hold them there for 30+ minutes?
Have you tried holding them at 13.8-14.4V in parallel for a week?

I realize you would prefer to get support for your products, but the above may be a means of you getting value out of what you have.

 

[crustacean]

You've said your peace. Please refrain from essentially making identical posts in other threads. Cross posting is at a minimum poor forum etiquette.

Good point. I think I just don't want anybody else to be ripped off by this incredibly frustrating company.

That out of the way...

To give you a comparison, a Battleborn user saw his battleborn battery drop to about 50Ah of capacity simply because they never fully charged them and the cells never entered the balancing phase, so over the course of 3 years, the cells lost their charge at different rates and one or more cells had dropped to 50% when others were at 100%. After holding their battery at 14.2V+ for 1-2 weeks to allow balancing, the battery delivered > 90Ah.

This may be a major contributing factor to your experience.

"Light use" implies that you were not regularly cycling any of these batteries.

Did you regularly charge your batteries to 14.4V and hold them there for 30+ minutes?
Have you tried holding them at 13.8-14.4V in parallel for a week?

I realize you would prefer to get support for your products, but the above may be a means of you getting value out of what you have.

Your balancing point is an interesting one though. I hadn't considered it. I actually wonder if the fact that one battery was dying rapidly could have affected the slightly newer and stronger battery. They were connected in parallel so it is certainly a possibility based on my limited understanding. The fact that one battery wouldn't accept more than 11.9 volts might have have limited the performance of the other battery? Is that possible?

Any thoughts on what my path forward should be? I can't just replace the one remaining bad battery with some other brand because then I have an unmatched set. Obviously I won't buy another HQST because they would be instantly be unbalanced in addition to the ethical issue. Do I just need to start over with a new bank from another company?

 

[sunshine_eggo]

Good point. I think I just don't want anybody else to be ripped off by this incredibly frustrating company.

I get it. A dedicated post with HQST in the subject line is going to get more search attention than your replies.

Your balancing point is an interesting one though. I hadn't considered it. I actually wonder if the fact that one battery was dying rapidly could have affected the slightly newer and stronger battery. They were connected in parallel so it is certainly a possibility based on my limited understanding. The fact that one battery wouldn't accept more than 11.9 volts might have have limited the performance of the other battery? Is that possible?

It's very hard to say. You didn't answer my question.

Did you regularly charge your batteries to 14.4V and hold them there for 30+ minutes?

If the answer is "no," than balance is almost certainly a factor.

Any thoughts on what my path forward should be?

Yes.

Have you tried holding them at 13.8-14.4V in parallel for a week?

This ^

It's a nuisance, and it may require you to get creative with a voltage source, but it answers the balance question. If your battery capacity increases, it's confirmation of imbalance.

If you don't have a suitable voltage source, you can try lightly discharging (5Ah or so) and then recharging at a very low rate.

I can't just replace the one remaining bad battery with some other brand because then I have an unmatched set.

That's what manufacturers tell you to discourage you from buying from their competition. The official line? Same brand, same chemistry, same capacity, same age, etc.

The reality is that MANY violate all of the above on a regular basis with great success.. sometimes even paralleling LFP and lead-acid. Putting two different aged/brand 12.8V 100Ah LFP in parallel is a non-concern.

 

[crustacean]

Sorry. You're correct I didn't answer your original question.

For the past 14 months I've had 2 batteries mounted in parallel in my van while I travel. They were brand new when I began. Nearly every day they were topped off to 14.7 volts via solar/alternator. Last spring I saw a sudden drop in capacity and quickly determined that one had completely and suddenly died. I panicked and replaced it with a new HQST battery from Amazon (which was physically larger than my first two). The system worked fine for another six months. The last month I have been unable to charge the bank above 13.2 volts and my capacity was extremely low.

This month I finally was in a location long enough to buy the capacity tester recommended by Will and a 120V wall LiPo charger. For each battery I separated it from the van, charged it with the LiPo charger to full capacity, and then did a full capacity test of each twice. This test revealed the results that I mentioned above.

Thanks for your patience with my frustration. I appreciate the insights as well.

 

[sunshine_eggo]

Sorry. You're correct I didn't answer your original question.

For the past 14 months I've had 2 batteries mounted in parallel in my van while I travel. They were brand new when I began. Nearly every day they were topped off to 14.7 volts via solar/alternator. Last spring I saw a sudden drop in capacity and quickly determined that one had completely and suddenly died. I panicked and replaced it with a new HQST battery from Amazon (which was physically larger than my first two). The system worked fine for another six months. The last month I have been unable to charge the bank above 13.2 volts and my capacity was extremely low.

Given the daily charging, I would not necessarily conclude balance is an issue.

Technically, 14.7V is over what you should charge LFP to. 14.6V is the max theoretical and 14.4V is preferred. The assumption is that the BMS engaged protection and prevented damage. In cheaper batteries and BMSs, frequent triggering of protection can cause the FETs to fail and weld closed, i.e., they don't protect anymore. This might have allowed the fully charged cells to be regularly over-volted causing deterioration and failure.

I would figure out how to limit charging to 14.4V and float to 13.5V.

This month I finally was in a location long enough to buy the capacity tester recommended by Will and a 120V wall LiPo charger. For each battery I separated it from the van, charged it with the LiPo charger to full capacity, and then did a full capacity test of each twice. This test revealed the results that I mentioned above.

When you plug the charger into the wall and measure the output leads with a voltmeter, what voltage is it putting out?

Thanks for your patience with my frustration. I appreciate the insights as well.

No worries. You have a right to have a chapped ass over this.

 

[Alkaline]

Open them up and put an active balancer to see if that helps.

 

[diytx]

50Ah of capacity simply because they never fully charged them and the cells never entered the balancing phase

I am very new so starting to learn the in's and out's ... can you expand on this please. Say I buy panels, I buy a rack of server batteries, I then need to charge the batteries to 100% out of the gate otherwise they will never balance? My Tesla sits @ 80% for optimal longevity. Am I too assume that you want to deal server rack LiFePo4 batteries the same way? Set max charge to 80%?

 

[sunshine_eggo]

I am very new so starting to learn the in's and out's ... can you expand on this please.

LFP batteries must be regularly charged to elevated levels to properly keep the cells balanced. Balanced = same SoC - NOT voltage. Voltage only correlates to balance above 3.40V.

The LFP voltage curve is almost flat, this tiny changes in voltage can be large changes in SoC.

Say I buy panels, I buy a rack of server batteries, I then need to charge the batteries to 100% out of the gate otherwise they will never balance?

Pretty much. Due to absurd costs associated with it and the high likelihood that a new battery would lose its top balance between manufacturing and deployment, they don't bother.

My Tesla sits @ 80% for optimal longevity.

Depending on which Tesla, most use NCA chemistry, which is VERY different from LFP. It has a very high voltage to SoC correlation at all levels, so it's very easy to target a voltage-based SoC operating range. It's nearly impossible with LFP.

Even if your Tesla has LFP, the BMS managing the Tesla is infinitely more advanced than anything in a server rack battery BECAUSE Tesla knows every single technical detail about their cells whereas the battery builders do not have that level of cell data since they don't MAKE the cells.

Am I too assume that you want to deal server rack LiFePo4 batteries the same way?

Nope. It's not a Tesla.

Set max charge to 80%?

Nope. No practical way to do this without potentially losing capacity over time due to cell imbalance.

 

[Texas-Mark]

Nearly every day they were topped off to 14.7 volts via solar/alternator. Last spring I saw a sudden drop in capacity and quickly determined that one had completely and suddenly died.

IMO the main issue is with the 14.7 volt charge. That's too high. BMS will trip (the one you think died), or damage to the cells can occur if the BMS is allowing it. As noted above 14.4 volts is really the max, and it is still likely an out of balance cell will still trip the BMS before that voltage.

 

[Bigbillsd]

I stupidly purchased 3 HQST 100Ah batteries from this scam of a company.

My first battery died after 6 months. No customer support. My 2nd battery died after 14 months. Technically it is not dead but 6Ah capacity at 11.9 volts is basically dead. My third battery delivers 80Ah after only 6 months of light use. RUN AWAY FROM THIS COMPANY! Seriously if you even consider buying from a company without a phone number then I can not help you! Every email to them has been unreturned.

It says they have a 10 year warranty? I was shocked by their $199.99 price the other day on Amazon.

 

[reader2580]

It says they have a 10 year warranty? I was shocked by their $199.99 price the other day on Amazon.

Any company can claim they have a ten year warranty. The question is do they actually have any intention of honoring the warranty?

I have been chasing SOK for six weeks now trying to get a dead 48V100 battery dealt with under warranty. No luck yet.

 

[augiedoggy]

I stupidly purchased 3 HQST 100Ah batteries from this scam of a company.

My first battery died after 6 months. No customer support. My 2nd battery died after 14 months. Technically it is not dead but 6Ah capacity at 11.9 volts is basically dead. My third battery delivers 80Ah after only 6 months of light use. RUN AWAY FROM THIS COMPANY! Seriously if you even consider buying from a company without a phone number then I can not help you! Every email to them has been unreturned.

With that many failures I am questioning how this actually happened. It would seem something caused these failures on ALL 3 of the batteries and I doubt its because they were all defective. There has to be some non typical variable here they were subject to to take out all 3 so quickly..

EDIT .. should have read on, looks like this thread is a few months old and you were not specifically using a lithium charger but rather an alternator (which is not even true DC current) and solar with unspecified parameters rather relying on the bms to protect the batteries from overcharging. While its true the bms should have prevented this its not good practice and Ive read advice over and over that it should not be the norm. I would think a voltage of 14.7 could cause one cell to go over 3.65 more easily and kick off the bms disabling the battery at least until that cell drops to the safe charging voltage.

What charge controller are you using? how many watts of solar and are you using a lithium charge profile for lifepo4?

The amazon reviews appear to be mostly of an older version battery than they offer now but they dont look good.