EVE vs CATL cells

[Don Fukushima]

This forum mentions EVE cells far more than CATL, by a lot. I'm going to build a new LiFePO4 pack and down to these two brands. My understanding is A grade EVE cells are on the open market but the auto industry has the lock on the A grade CATL cells and what is on the open market are grade B at best. If that is the case, then it's a moot point to ask if there is a choice at all.

[alexander ross]

Only Shenzhen Luyuan Technology Co., Ltd Alibaba seller as grade A eve  cells to my knowledge. Anyone else is grade b or used and is lieing. 

Idk if there is new grade a cells in the last 2-3y? 

I not seen nor searched much for catl. I think these less on the open market?? 

[Dacian Todea (electrodacus)]

CATL is the largest battery manufacturer in the world and likely has superior batteries than EVE but CATL cells are less available for DIY other than used or rejected cells the get on to black market.

EVE is also probably mentioned more on this forum since they are the most available and I also got a set for testing so probably I did quite a few posts about them.

Tho my cells while new in the sense of fabrication date do not meat the spec (lower capacity) so likely it was some rejected batch that got on to black market. I'm OK with them as they where inexpensive and new not used.

It remains to be seen what the calendar aging degradation is for this cells but for that I need to wait at least a year since my initial capacity test that I made this spring so next year in spring I can have an idea about the combined calendar aging and cycling degradation. Since cycling degradation will be insignificant most of the degradation will be due to time. 

[Don Fukushima]

https://batteryhookup.com/products/new-catl-modules-with-20x-3-2v-280ah-prismatic-17-92kwh-150-kwh

This is the specific battery I am considering that claims to be grade A CATL. These folks are a reliable and honest vendor and fairly describe what the offer but they are still a reseller so the true origin and authenticity of the OEM and batteries is not certain.

The decision factor is if these are true grade A CATL cells then these are likely a better battery than EVE cells; the risk factor is not being 100% certified. That being said, buying EVE cells can result in substandard quality too.

[Don Fukushima]

https://batteryhookup.com/products/2x-new-catl-3-2v-280ah-cells-recovered-from-modules

On Thursday, June 8, 2023 at 11:41:53 AM UTC-7 Don Fukushima wrote:

Here's the link to the broken down pack, 2 280 cells at $270 or $130 each

[Oberon Robinson]

Don, I bought batteries from Battery Hookup and was not disappointed.  Shipping is WAY faster and you have some recourse if there's anything wrong.  You're always taking a bit of a gamble with this kind of purchase, but if BH says they are brand-new then chances are good that you'll get at least close to the stated capacity.

[John Stephens]

I found this mfr to be excellent (the img above was my initial purchase and I've been back twice since).

If anyone is interested in CATL's try this link https://szxuba.en.alibaba.com/

cheers all!

[Don Fukushima]

Thanks Oberon,
My experience with BH has been good too so far.

This link goes to ad where they openly advertise grade A CATL cells. This sort of thing is what makes me suspicious for two reasons. Dealing with unknown (to me) China direct companies and the claims they make about the grade a product which many say are not available outside factory to OE companies. Always need to be extra cautious when making expensive and heavy products, shipped internationally.

https://www.alibaba.com/product-detail/SZXUBA-Grade-A-Capacity-Tested-Catl_1600740345850.html?spm=a2700.shop_plgr.41413.2.446a3e5fUoBWXw

[Dacian Todea (electrodacus)]

What will you do with a 20s battery ?

The terminal are welded it will be next to impossible to do any modifications.

That is likely specifically designed for some sort of small electric vehicle about 64V nominal.

[Don Fukushima]

This link shows the cells have been broken out from the 20s packs and sold singly. They cut the bus bars. Questionable what the true source of these are and if actual grade A cells. Maybe that's why the vast number of builders go with EVE cells. 

https://batteryhookup.com/products/2x-new-catl-3-2v-280ah-cells-recovered-from-modules

[Flint Smith]

What convinces me that these are A-grade cells is that a company actually built them into car batteries.

The ones I bought have EVE factory welded 2-bolt contacts, which I took to be evidence that they had gone farther down the QA path.  Actual modules sounds like strong evidence.

I also have had positive interactions with Battery Hookup.  Things they sold as "new" have been new as far as I could tell.

[Don Fukushima]

OK, convinced. Placing order for the CATL cells. thanks for the insights.

[Casey & Gina]

Docan Tech came highly recommended on diysolarforum for whatever that's worth, and I bought CATL cells from them directly (not yet put to use though).  A friend of mine bought EVE cells through them and they've been great, but they didn't have US stock available when I ordered and I thought I was in a bigger hurry than I was and needed them quick, haha...they're still in the boxes months later.  They do sell grade B as well but have different pricing and seem to be honest about it.  I'd be interested in knowing how to test whether cells meet their spec...