As noted in yesterday's thread about QR tag conflicts, I just received four EVE280k cells from EEL Battery via Amazon. These are my first cells for a build, but I've had SLA with off-grid solar for several years. Basically, one of these cells had apparently been shorted by a bus bar prior to shipping.
The cells arrived in two boxes, two to a box. The first box had a single, loose bus bar laying on top of the packing foam right under the top cardboard. I thought that was a little weird, but it's the type with a dogleg in the middle (flexible?) and was well-pressed into the foam. It couldn't have been floating around the box once sealed. Under that top piece of thick foam, I unexpectedly found that the cells had the new, large, two-hole terminals. Those on one had clear signs of arcing. The cells were packed side-by-side without foam between them; it was to one side of the pair.
I didn't put 2+2 together until I opened the second box. There a pair of bus bars and screws (8) were in a static bag on top of the foam under the cardboard top. The cells had the same large terminals and were packed with a thick piece of foam between them. "Ah, ha," thinks I. This was how the first box was originally packed. Back in the first box, I found a handful of loose screws under the cell with terminal arcing. Like the bus bar on top, they were so pressed into the foam once the cell was placed on top of them that they couldn't have been bouncing around during shipment.
Long story a bit shorter, I found that the loose bus bar also had signs of arcing - ones that exactly reflected marks on the terminals. It's clear to see. My guess is that they pulled a bar out of the pack to leave three for 4S, dropped it on the terminals, got the inevitable results, and quickly repackaged the box neglecting to put the foam between cells, but rather outside of them so everything was still tight in the foam.
The good news is that all four cells measure identical voltage and internal impedance (1.118M ohm). EEL has offered to extend the warranty to five years.
Keep 'em or not? Not a reassuring first-time experience. I'm still mulling over what to do about the QR label claiming they are EVE cells and the code claiming they're CATL. No answer from EEL on that, yet.
The cells arrived in two boxes, two to a box. The first box had a single, loose bus bar laying on top of the packing foam right under the top cardboard. I thought that was a little weird, but it's the type with a dogleg in the middle (flexible?) and was well-pressed into the foam. It couldn't have been floating around the box once sealed. Under that top piece of thick foam, I unexpectedly found that the cells had the new, large, two-hole terminals. Those on one had clear signs of arcing. The cells were packed side-by-side without foam between them; it was to one side of the pair.
I didn't put 2+2 together until I opened the second box. There a pair of bus bars and screws (8) were in a static bag on top of the foam under the cardboard top. The cells had the same large terminals and were packed with a thick piece of foam between them. "Ah, ha," thinks I. This was how the first box was originally packed. Back in the first box, I found a handful of loose screws under the cell with terminal arcing. Like the bus bar on top, they were so pressed into the foam once the cell was placed on top of them that they couldn't have been bouncing around during shipment.
Long story a bit shorter, I found that the loose bus bar also had signs of arcing - ones that exactly reflected marks on the terminals. It's clear to see. My guess is that they pulled a bar out of the pack to leave three for 4S, dropped it on the terminals, got the inevitable results, and quickly repackaged the box neglecting to put the foam between cells, but rather outside of them so everything was still tight in the foam.
The good news is that all four cells measure identical voltage and internal impedance (1.118M ohm). EEL has offered to extend the warranty to five years.
Keep 'em or not? Not a reassuring first-time experience. I'm still mulling over what to do about the QR label claiming they are EVE cells and the code claiming they're CATL. No answer from EEL on that, yet.