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12.8V 100Ah GoKWh Review

sunshine_eggo

Happy Breffast!
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Oct 26, 2021
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Location
HBR, USA (6500' in ENE AZ)
Full disclosure: I was contacted through the forum by steve@lightning-energy.cn to review the subject battery. It was supplied to me for free. I think this is the ONE time it's ever paid me to be a post whore.

Here's the manual:


Agreed to do the review 11/21/23.
It was allegedly shipped 11/24/23.

I gotta be honest, I figured it was BS. After a couple months, I just assumed it was a fishing expedition that flopped.

Whelp... I was quite surprised when the battery arrived on 2/8/2024. I mean, I thought "WTF is this box on the porch? I didn't order anything from China!"

Lookey there!

1711688640074.png


Bolts:
1711688673601.png

Well packaged:
1711688718552.png

Yep. It's a battery:

1711688779202.png

Came with a "fancy" voltmeter/SoC meter.

5.31mΩ per the YR1030. Meh, but I honestly don't know what's typical on a packaged battery.
1711688852666.png

Yep. I tried to cut it open. Found out there were screws under wee tiny yellow plugs that were nearly invisible. My 53 year old eyes aren't what they used to be... 😭

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BMS:
1711688952938.png

BMS 2:


1711688992236.png

Temp sensor/pouch cells:
1711689044333.png

Charged @ 14.4V/10A with temp sensor in ice water, and it charged with wild abandon. NO CHARGE PROTECTION, BUT... The specs don't say it does. See towards the bottom for more commentary on low temp protection.

Discharged @20A to 10V:

1711689172978.png

43.93Ah, so about 44% SoC - above the 30% for hazmat shipments.

Since that charge terminated normally without BMS termination and a resting voltage of 11.06, I discharged to 9V to trigger low voltage protection:

1711689289646.png

BMS triggered protection and battery showed 1.43V resting.

I set my charger to track voltage and applied the 30V/10A power supply to the battery (I do not recall the current):

1711689380686.png
I periodically removed the power supply to see if it would hold voltage. As you can see, it didn't hold until about 4 minutes of charging.

Since I didn't want to subject my charger to an over-voltage protection event, I simply used it to log voltage while I charged with the 30V/10A supply:

1711689500092.png

Since this was at 10A, time scale is roughly equivalent to SoC/10.

I'm the first to jump into the conversation to say that almost all batteries arrive imbalanced. What really surprised me is this one... didn't. As you can see, it ran right up to just above 14.6 (14.65V per the data table) before it jumped to 15.66V (power supply setting) two seconds later. I left it there and allowed it to cycle on and off for about 1.5 hours... because... you know... free battery!

So, the conclusion is that whatever criteria the BMS is using, any cell imbalance that may be present does not impact the ability to charge to peak voltage.

I ran a 30A discharge to 10V:
1711689774210.png

105.5Ah.

Since I demonstrated the battery was balanced, I was willing to log a 20A charge to 13.6V to see how close I could get to 100%:

1711689843562.png

104.6Ah input or 99.7% SoC assuming 100% charge efficiency. Just needed a 5 hour absorption period and a 0.02A tail current.

Overall, aside from somewhat cheap construction (BMS just taped on), have no complaints for a $270 battery.

Now for the sticky bits...

In communication with Steve, he made the following claims:

The battery has low-temperature charging protection.
The battery can be charged at -20 ℃, and we have set the low-temperature charging protection to -10 ℃.


This is in conflict with the specification that indicates charging from 0-45°C (again, I charged without restriction with the temp sensor in ice water).

When I presented that bit from the spec, he responded with:

I have confirmed with several engineers that -10 ℃ is not harmful to battery charging. However, charging at -10 ℃~0 ℃ will be very slow.

I do not believe it, but I didn't disprove it, so we'll just let that stand as an unconfirmed claim. For best results, I recommend one provide their own low temp charge protection.

The voltage/SoC meter is a nice touch. Unfortunately, the manual is VERY poor in its description of how to program the meter. I rendered it useless inadvertently, but managed to finally get it figured out. Having a voltmeter is handy, and I'm confident that one could program the SoC parameters to their satisfaction to represent a good guess at a resting SoC.

Pros:
  • Well packaged.
  • Bolts included
  • Cells were received in balance.
  • Tested > 105Ah
  • Over-voltage and under-voltage protections work.
  • Voltmeter/SoC gauge
Cons:
  • Shipping delay
  • Pouch cells
  • Lower quality construction, but typical of this price point - nothing overly concerning (better than older versions of this battery I've seen on YouTube)
  • Unconfirmed claims of low temp charging protection at -10°C.
  • Voltmeter/SoC gauge poorly documented, easy to mess up, and tricky to program.
Conclusion:

If I were in the market for an inexpensive 12.8V 100Ah battery without low temp charge protection, this would be on my list for consideration.

Review continued:

 
Last edited:
I have confirmed with several engineers that -10 ℃ is not harmful to battery charging. However, charging at -10 ℃~0 ℃ will be very slow.
Well that's new..
everything we know from everyone & every manufacturer is a lie! steve out there dropping the truth we can charge below freezing all this time! abandon sodium ion and go full LFP!

I wonder how they overcame the "plating of metallic lithium can occur on the anode during a sub-freezing charge"
also I want free batteries..
 
I am curious how much time it took from your life for this review. Is it worth your hourly rate?
 
Well that's new..
everything we know from everyone & every manufacturer is a lie! steve out there dropping the truth we can charge below freezing all this time! abandon sodium ion and go full LFP!

I wonder how they overcame the "plating of metallic lithium can occur on the anode during a sub-freezing charge"
also I want free batteries..

The only way you get safe low temp charging is via Yttrium doping of the cathode.
 
The only way you get safe low temp charging is via Yttrium doping of the cathode.
Yttrium is almost always found in combination with lanthanide elements in rare-earth minerals and is never found in nature as a free element. 89Y is the only stable isotope and the only isotope found in the Earth's crust.
Damn I guess the guy on the street corner can't give me that kinda cathode dope...

Looks like those batteries are called "LYP"
LiFeYPO4

hey man maybe the ones you got are actually LYP?
 
I am curious about your comment concerning programing the voltage/capacity LCD on the battery. I just got in yesterday a similar (24v) battery that its readout showed 25.1v and 83% capacity. It presently is on a 3a charger up in my shop which hopefully overnight has achieved a full charge. All it has on the LCD display is a push button with the on symbol. Pushing it displays voltage and capacity for a few seconds before cycling off.

Thanks for the review. Sounds like the one you got is decent.
 
Just to be clear on nomenclature:

Before you were a post slut, for free. Practically servicing the entire 7th fleet while it was in town judging by your post count.

Finally you are a certified post whore 😎.

But you obviously had a well documented honest roll in the hay with this battery.
 
What don't you like about pouch cells?

They are generally regarded as inferior to prismatic. As prices have decreased, many battery builders have switched to pouch even within the same model as the price drives lower.

What would you use for external low temperature protection?

What else of course?!... Victron MPPT and Inverter/chargers can be set to not charge below a set temperature to protect LFP.
 
Went to edit my review and discovered that there's a 15 image post limit...

UPDATE:

steve@lightning-energy.cn contacted me and provided the following info:

1711723713172.png

The cells are Grade A BYD cells conforming to the above. The BMS is also JBD.

I'm tempted to put it in the deep freeze and see what happens.

Others have used freeze spray to chill the sensor to very low temps and charge protection did occur. The temperature was somewhere below -15°C because -15°C was observed with a cold pack on the temp sensor, and it didn't trigger protection.
 
oh so now you can do -30 instead of -20 with a -10 switch.. hmm it just gets better

@sunshine_eggo you can get dry ice at walmart or some other grocery store, that will bring you down really low in temp

IT'S LIKE $2
 
Went to edit my review and discovered that there's a 15 image post limit...

UPDATE:

steve@lightning-energy.cn contacted me and provided the following info:

View attachment 205529

The cells are Grade A BYD cells conforming to the above. The BMS is also JBD.

I'm tempted to put it in the deep freeze and see what happens.

Others have used freeze spray to chill the sensor to very low temps and charge protection did occur. The temperature was somewhere below -15°C because -15°C was observed with a cold pack on the temp sensor, and it didn't trigger protection.
Log into that JBD and see what the low temp cutoff is set to. I bet it's not correct.

Edit - now I see the BYD spec of - 30C, wow.
 
I can add that I was also contacted by Steve and was also sent a battery. I charged it and discharged it and it performed the same. Unfortunately my discharge tester is broken but from rough calculations the capacity is the same as stated.
 

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