Li-Ion Battery Quality Report

[DaveE]

OK, I guess I'm only buying name brand batteries now.

Lumafield makes CT scanners for industrial engineering and production testing. They've released a report on the quality of Li-Ion batteries that they surveyed (18650 cells), which I thought was really interesting.

https://7802750.fs1.hubspotusercont...Guides/Batteries/Lumafield Battery Report.pdf

 

[berkeman]

Yikes!

 

[Greg Bernhardt]

Given the fire risk of lithium, there is little reason to go cheap.

 

[Ken Fabian]

Regulated and enforced safety standards seem necessary, ie the cheap counterfeits should be detected and rejected. De-funding regulatory agencies and industry 'self regulation' looks short sighted; I suspect the insurance industry favors enforced standards as will most of the major manufacturers.

A lot of cheap batteries have exaggerated capacity as well, so not such a bargain as might seem even before considering expected working life and fire risks.

Not sure it is useful to go by averages for determining our risks; whilst I may have some items that may contain poor quality batteries (a cheap electric shaver comes to mind) most of the batteries come from reputable sources. The largest (solar batteries and electric ride on mower) are LFP type that are less flammable. Seems possible we'll see a shift to sodium chemistry - they are coming onto the market and whilst not having the storage density of NMC are not much short of LFP and CATL is claiming very long working life (5,000 to 10,000 cycles) and superior low temperature operation.

But there are a lot of batteries already in most homes with more all the time and just by their numbers the risks rise - and not only from battery faults; chargers for them as well as the things they power have fire risks.

 

[Rive]

Given the fire risk of lithium, there is little reason to go cheap.

On the other hand, only the cheap batteries keeping some product prices low (and this is not only about this particular battery format - the low quality and very liberal parameters of cheap batteries is a quite widespread issue).

 

[russ_watters]

I'd been thinking of buying a new charger and batteries for AA devices. Looking online, it doesn't appear that any major manufacturer sells rechargeable Li-Ion batteries. So now I have to decide if I want a no-name or NiMh.

 

[sophiecentaur]

Regulated and enforced safety standards seem necessary, ie the cheap counterfeits should be detected and rejected

That video is truly scary but what to do about the problem? I imagine the CT technology will always be expensive; even for small items. I have an appointment for a CT scan on Saturday and I looked up the probable cost. It seems the NHS will be paying quite a few hundred quid for it. A scaled-down version for small components would be much cheaper but it would still be a significant part of the cost of a cell. A lot of money to be made for a certified service as it would be used by every industry you can think of.

One possible upside could be the cost of having your pet scanned if small scanners become more popular and lower cost. But don't hold your breath.

 

[Rive]

I'd been thinking of buying a new charger and batteries for AA devices. Looking online, it doesn't appear that any major manufacturer sells rechargeable Li-Ion batteries.

Erm... As far as I know there is just no suitable Li-based chemistry for the usual voltages associated with the AA format.

 

[sophiecentaur]

Erm... As far as I know there is just no suitable Li-based chemistry for the usual voltages associated with the AA format.

Warnings all over instructions for using portable equipment fitted with AA cells. They say their units will not work 'properly' with rechargeable.

 

[Rive]

They say their units will not work 'properly' with rechargeable.

Erm... That's a bit different.
Li-ion cells (rechargeable) works around 3.7V
Standard AA (Zinc-Carbon, non-rechargeable) is around 1.5V
There is 'high energy' AA, with Li content but still not rechargeable at nominal 1.5V, though during usage they run a bit lower than standard cells
Rechargeable AA NiMh cell are around 1.2V

So Li-ion based rechargeable is just too high voltage (without electronics)

Rechargeable AA is lower voltage and indeed, some electronics may complain about low voltage, but still, in AA format NiMh is the only practical/cheap way. Many modern equipment tolerates this voltage (at least in normal circumstances - at winter it is a royal PITA).

 

[russ_watters]

There is 'high energy' AA, with Li content but still not rechargeable at nominal 1.5V, though during usage they run a bit lower than standard cells
Rechargeable AA NiMh cell are around 1.2V

So Li-ion based rechargeable is just too high voltage (without electronics)

That's interesting but there are a bunch of no-name 1.5V AA rechargeable Li-Ion batteries/chargers for sale on Amazon. Any thoughts on how they might work? This one does appear to have a circuit board on top, and lists its capacity in mWh instead of mAh. So maybe that's what it is.

https://www.amazon.com/dp/B0D4M581B3?tag=pfamazon01-20

 

[Rive]

Any thoughts on how they might work?

They are the 'not without electronics' ones. A small Li-ion battery (at 3.7V) with a charging electronics and a step-down converter (to provide the 1.5V) is fitted in the AA case.
Some has dedicated charger, some has USB slot or similar, or an USB plug hidden under a cap... Pretty creative, actually

It's a cheap niche (exactly the one where you can expect a trash battery inside with overstated parameters), so don't expect a quality product. But if you don't need much peak current, then it's a passable 'forever' replacement.
(I won't hold my breath for fire safety, though...)

Ps.: just to be clear, these are devices, not exactly batteries. At least, in my book.