Best 280-304 to buy right now?

[acolunga07]

I was trying to decide between EVE304 “Grade A” vs CATL280 “Grade A” from Docan (Houston -Amy). But, based on multiple threads and Amy’s messages, it appears that these are “Grade B” EVE 320 or “Grade B” CATL304. “Grade” because it seems the whole grade A/B thing is a bit of a scam, but they are most certainly not EV grade (which we’ll just call “Grade B” for now.

Messages from Amy:
“CATL 280Ah real capacity around 295+”
And again on another day:
“Yes we have CATL 295Ah+ in USA stock”
And on another day discussing here EVE cells:
“EVE 304Ah are many people called 320Ah due to the tested out capacity is over 320Ah”

Needless to say, I don’t trust Amy (Docan) in spite of having a previously good reputation (as is well documented on this form for previous years). I

am now leaning towards
https://www.18650batterystore.com/ since they are at least honest about selling “Grade B” cells and they are cheaper. They sell CALB 305, EVE 304 or CATL 302 cells for $129. All are tested/sorted/matched and guaranteed for 30 days. Shipping for 16 cells (4P4S) pack is $148 so the overall cost is actually cheaper than Docan which is local (I’m in houston).

It looks like the EVE 304 are currently sold out, so it’s between:
18650’s CATL 302 Grade B
18650’s CALB 305 Grade B
Docan EVE 304 “Grade A” (probably B)
Docan CATL 280 “Grade A” (probably B 302s)

What do y’all recommend?

 

[time2roll]

If spending money today I would have the EVE with the factory two hole block terminals.

https://www.18650batterystore.com/collections/lifepo4-prismatic-cells/products/eve-lf280k
If 304 was available with this terminal I would get the larger cell.

If I could pick up same from Docan in person due to location that would be my choice. Easy to exchange in person if an issue arises.

I could be tempted to drive to GA to avoid shipping issues. Good excuse for a road trip.

 

[MrM1]

I just got 16 EVE 304s out of Huston from Amy at Docan. Smooth transaction, 3 days to fl. Good price. Excellent condition and packaging . Excellent communication.

Cells look new. Unused condition. I'm sure they're cells that didn't make the EV cut. I'm ok with that. When doing the first charge with bms (pre top balance), I got no runners out of 16 until they all reached 3.56v +. Now top balanced, they hold a delta of less than 0.008 in use and a delta of 0.010 at 3.5v

I'm happy with the sale and service. This is my third large purchase from Docan in 18 months . Experience was same each time. I don't get caught up in the A/B marketing lingo. But I'd rather have these than others grade B cells.

 

[MrM1]

Look around here . You'll find some members here that had issues with the Grade B cells you mentioned. There are always some orders that have issues. I look for patterns.

 

[Alkaline]

$130-140 + shipping for grade B are a rip-off. Would not pay more than $90/cell for grade B regardless of the place.

 

[klempak]

I am in the same situation. Either go with Docan or 18650. I also have one more option to buy from srikobatteries.com in person since I am in IL, just not sure what to look for besides bloating and perhaps test the voltage. Sriko currently have EVE 300ah and Lishen 272ah. Sriko informed me that their supplier is stating these are Grade A cells, not sure what to think of it.

 

[acolunga07]

$130-140 + shipping for grade B are a rip-off. Would not pay more than $90/cell for grade B regardless of the place.

To be clear on pricing, it would be:
18650’s CATL 302 Grade B $129
18650’s CALB 305 Grade B $129
Docan EVE 304 “Grade A” (probably B) $138
Docan CATL 280 “Grade A” (probably B 302s) $132

18650 has a $148 shipping, no tax, $2212 total
Docan charges a $55 payment fee, no tax, $2167 or $2263 total

 

[acolunga07]

I just got 16 EVE 304s out of Huston from Amy at Docan. Smooth transaction, 3 days to fl. Good price. Excellent condition and packaging . Excellent communication.

Cells look new. Unused condition. I'm sure they're cells that didn't make the EV cut. I'm ok with that. When doing the first charge with bms (pre top balance), I got no runners out of 16 until they all reached 3.56v +. Now top balanced, they hold a delta of less than 0.008 in use and a delta of 0.010 at 3.5v

I'm happy with the sale and service. This is my third large purchase from Docan in 18 months . Experience was same each time. I don't get caught up in the A/B marketing lingo. But I'd rather have these than others grade B cells.

How long ago was that purchase?

 

[acolunga07]

If spending money today I would have the EVE with the factory two hole block terminals.

https://www.18650batterystore.com/collections/lifepo4-prismatic-cells/products/eve-lf280k
If 304 was available with this terminal I would get the larger cell.

If I could pick up same from Docan in person due to location that would be my choice. Easy to exchange in person if an issue arises.

I could be tempted to drive to GA to avoid shipping issues. Good excuse for a road trip.

That’s a 12 hr drive one way for me.

Why the strong preference for the EVE with two holes? Is it because they are Grade A (if we trust 18650’s claim which is probably true because they are truthful about their other B cells). Or is it the two holes? What advantage does that have?

 

[Alkaline]

EVE official grade A has 2 holes, but these can cause issues apparently because of uneven torque on the cells:

the ones with the holes caused issues, uneven torque resulted in a lot of heat being built. Plus people use the grub screw in them and use threadlocker that can leak onto the main terminal area which will then result in poor electrical connection and even more heat/bad readings

So they are having issues, maybe using he dual hole but only use 1 screw per terminal?

 

[MrM1]

How long ago was that purchase?

2 weeks ago

 

[MrM1]

I purchased 16 EVE 230Ah from her in the fall of 21' after the Michael group buy debacle (don't ask)
- Huston. Flawless

I purchased a 34 EVE LF280k from her in late Dec 21'
- from China. Arrived on schedule
- purchased 2 extra just in case. Not needed
- built up in fall 22'
- placed into full service Jan 23'
- flawless

Purchased 16 EVE 304Ah 3 weeks ago.
- Huston
- paid for on Thursday, arrive on Monday, built by following Sunday.
- been in service 4 days.
- flawless

 

[Quattrohead]

I would not reward a business that is "flighty" with the specifications of the product.

 

[MrM1]

But I'm no shill or fan boy. Any seller can have issues. Some are more shady than others, but user experiences vary. YMMV

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[acolunga07]

I went ahead and purchased the EVE304 locally. Amy price matched 18650 for me. I’ll pick up on Monday and report in the results of the capacity testing.

Anybody local in houston have testing equipment I can borrow?

Advice on what to buy to do individual cell testing as well as overall pack testing?

I have multimeters and dc power supplies at work. From what I’ve read on here, it seems like I should charge it up as a 4P4S 12v pack first to like 85%. Then reconfigure to 16P and charge to 3.6V? Or thereabouts? And then buy/borrow something to capacity test the cells?

 

[klempak]

I went ahead and purchased the EVE304 locally. Amy price matched 18650 for me. I’ll pick up on Monday and report in the results of the capacity testing.

Anybody local in houston have testing equipment I can borrow?

Advice on what to buy to do individual cell testing as well as overall pack testing?

I have multimeters and dc power supplies at work. From what I’ve read on here, it seems like I should charge it up as a 4P4S 12v pack first to like 85%. Then reconfigure to 16P and charge to 3.6V? Or thereabouts? And then buy/borrow something to capacity test the cells?

So how much did you pay per cell ?

 

[WindWizard]

The way I look at it may be different than others. I purchased 112 Cells from Docan and my experience mirrors @MrM1 experience precisely. The Cells work and as far as giving them a grade, to me is just a waste of time.

Now that you purchased your cells then you can either test them to death and then say. Wow they have 290 amps!! or darn they only have 270 amps.

Now a lot of that has a lot to do on how you test them. There are a ton of variables to consider:

1- How accurate is your test equipment?
2- After the Cell reaches full charge of 3.65 Volts, do you stop charging or do you wait for the current to reach zero amps?
3- What is the load current that you use to discharge the Cell?
4- When the Cell voltage reaches 2.0 volts, do you hold the voltage and wait for the current to reach zero amps?

There are probably a lot more variables that I am not considering. It just takes a ton of time and work. If you can't find a Cell tester its going to cost you over $200 for something that you may never use again.

An alternative which I used because I wanted to use my Cells right now and not later, connect them into a pack and start using them. I know it's a bold statement, but it does work. When the BMS show one of Cells over 3.4 Volts then it is time to start watching. Discharge it with a light to bring it down and not trip the BMS.

Spend your money on a Victron Smart Shunt and then you can measure the true capacity of your Cell pack.

 

[acolunga07]

The way I look at it may be different than others. I purchased 112 Cells from Docan and my experience mirrors @MrM1 experience precisely. The Cells work and as far as giving them a grade, to me is just a waste of time.

Now that you purchased your cells then you can either test them to death and then say. Wow they have 290 amps!! or darn they only have 270 amps.

Now a lot of that has a lot to do on how you test them. There are a ton of variables to consider:

1- How accurate is your test equipment?
2- After the Cell reaches full charge of 3.65 Volts, do you stop charging or do you wait for the current to reach zero amps?
3- What is the load current that you use to discharge the Cell?
4- When the Cell voltage reaches 2.0 volts, do you hold the voltage and wait for the current to reach zero amps?

There are probably a lot more variables that I am not considering. It just takes a ton of time and work. If you can't find a Cell tester its going to cost you over $200 for something that you may never use again.

An alternative which I used because I wanted to use my Cells right now and not later, connect them into a pack and start using them. I know it's a bold statement, but it does work. When the BMS show one of Cells over 3.4 Volts then it is time to start watching. Discharge it with a light to bring it down and not trip the BMS.

Spend your money on a Victron Smart Shunt and then you can measure the true capacity of your Cell pack.

Thanks for the practical feedback. I am planning to purchase multiplus 2 12V 3000W, Orion tr smart 12/12 30A, smart shunt 500, lynx disyributor and thinking about cerbo gx & gx touch 50 (either or or a raspberry pi running vemos OS). I will also get the REC ABMS for the battery.

Like you said, maybe it’s better/easier to test it as a pack. Unlike most, I think I would still be happy with 1200Ah or even 1180 (as opposed to the 1216 Ah that it’s suppose to be). I would have spent $3k on a battery pack that could have cost me $10k+ and I get the experience/joy of building my own.

 

[time2roll]

I would skip the test and put in service asap. How the cells interact with each other is the most important part anyway.
BMS with active balance will take care of the manual top balance. Battery monitor will verify capacity.

Unlikely they would take simple test results as warranty anyway. Unless the cell was way bad and very unlikely that they are.

 

[WindWizard]

. I am planning to purchase multiplus 2 12V 3000W,

Are you planning on a 12 volt systerm? The only practical reason I can see for a 12 Volt system is a RV application otherwise 48 volt is far superior in every way.