- Oct 10, 2021
Where would you purchase cells from these days?
Where would you purchase cells from these days?
For DIY the challenge (as I see it) is that the intel is always at least 3 months old. EG: Every time I look it seems like the people that were delivering the products as advertised 3 months ago are failing miserably today. It's like an ever spinning roulette wheel of who the good guys are.
To answer your question literally, I purchased last month on Alibaba from Amy Wan (highly recommended seller by members of this forum)
View contact details for Shenzhen Luyuan Technology Co., Ltd. including address, contact person, telephone and fax number.szluyuan.en.alibaba.com
Moderate risk, balanced performance, and lowest cost. What do you recommend?What do you value? There's no right supplier for everyone - decide how much you're willing to deal with, then we can provide pointers. I'd suggest describing your requirements. Something like the following:
Risk/customer service vs cost:
High risk: I'm all about up front cost, and want the cheapest deal, believing I can take up significant issues with my payment processor, but otherwise will accept whatever is sent and make the best of it, knowing there's no real warranty or after-sales support.
Moderate risk: I want a good deal, but I want to be able to talk to someone if something goes wrong, with at least a 90 day waranty. I'm ok with paying for return shipping if there's a warranty issue that I want resolved.
Low/No risk: I want great customer support and service - if I have a warranty issue I want a replacement, and I don't want to pay shipping - they sent a bad cell, they replace it at their cost. I want to be able to call or email and have issue resolution within 24-48 hours.
Performance vs cost:
Lowest cost: I want the most cost efficient cells and will jump if I find anything close to $100/kwh, and won't ask too many questions. I accept that the cells may not be matched in any way, will probably require frequent or always-on balancing. I accept that I'm only going to get the lowest grade of cells, and can only count on their internal resistance measurements, and a limited guarantee of capacity. Long shipping is fine to reduce the overall cost.
Balanced: I want a good deal, but I want the batteries to perform to specification, and require light or infrequent balancing. I prefer new but am fine with new old stock, or removed from new assemblies but never used. I'm not a big fan of long shipping times, but willing to trade shipping time for cost if the difference is high enough.
Highest performance: I want the batteries to be matched and new, traceable to a reputable manufacturer. I expect free shipping warranty returns if the capacity or internal resistance fall out of spec within the first 90 days (ideally a year or more). I want them delivered quickly.
DIY vs cost:
Lowest cost: I want the lowest cost and accept the responsibility of building the pack correctly, making it safe and secure, buying and connecting a BMS, and maintaining the battery by keeping an eye on it over time.
Balance: I want a kit or a supplier that will provide everything and support me through the process of building it. After that I want it to be fully self-sufficient, and provide an obvious alarm if there's a problem, with supplier support in that case.
Hands-off: I want to open the box, connect it, and use it. I want it to work seamlessly with my system, and have compatible communications. If there's a problem, I want the supplier to resolve it without much troubleshooting on my part, and replace it or provide a partial refund if it doesn't meet specifications.
Or whatever other requirements you have.
I'm very curious about grade b cells... I guess you could say I'm grade b curious lolI placed my order of 4 x EVE LF280K with Amy on June 7th. Shipment was two boxes (2 batteries per box) and box#1 arrived July 28th and box#2 followed the next day on July 29th (52 days delivery time to Toronto Canada).
The cells were described by Amy as "LF280K, brand new. Grade B —the voltage and internal resistance are matched, the capacity is not. The actual capacity is 275AH-284AH. QR code has B stamp , $111/pcs".
Shipping was $140 and final delivery made via UPS. Tracking number was provided when order was placed, but package could not be tracked until it arrived in Canada (by sea).
Transaction was super smooth and went without a hitch. Thanks to members of this forum for recommending Amy as a reliable and trustworthy source. Will definitely order from her again.
I'm a degenerate gambler, so I'm looking forward to running capacity tests on each cell to see if I got a good batch or not
Where do you buy grade b cells?That is a fair question Eric.
Only difference is the grade A cells from Amy are FULLY tested and come with an extensive test report and cost almost twice as much.
The lesser grade are exactly the same and come off the exact same production line and are only partially tested.
What you are paying for is the time and the equipment required to do all the extra testing.
You cannot do a full discharge test and a full recharge in just a couple of minutes.
It all costs, takes time and extra people to do, and that is what you would be paying for.
Unless its for some really ultra critical application, the grade A cells are just not worth it.
Even if the grade B cells were slightly sub standard, which would you prefer:
One fully tested guaranteed cell that has 100 % or more rated capacity.
Or two grade B cells for almost the same price that total up to have 180% to 200% (or more) of the rated capacity of one cell.
For us, grade B are the best deal by far.
Where do you buy grade b cells?
Regarding EVE 280AH cells, we have two grades to choose from (both LF280K, brand new):
Grade A --fully matched, meeting the specification is the most basic requirement, and its performance is often higher than the specification. It could be with new terminals, current price: $148 /pcs,discount price $146/pcs
Grade B —the voltage and internal resistance are matched, the capacity is not. The actual capacity is 275AH-284AH. QR code is blurred,$111/pcs,discount price $109/pcs