So you think Samsung have battery problems?

[Nick]

Samsung are amateurs - NASA know how to do these things properly! They described it as "Explosive disassembly"

https://www.engadget.com/2016/10/28/lith...t-at-nasa/

Obvious really - never allow a RoboSImian on a 'plane

[Refugee]

Space craft were not the first flying machines to get infected with lithium syndrome.
Passenger aircraft beat them to it.

[Nick]

Lithium-based battery fires precede that too, but none of the 787's battery issues resulted in the loss of a plane, or "explosive disassembly"

[Mike Watterson]

The craziest thing is Lithium packs (Tesla's Elon Musk sells them) for home PV panels. Lead Acid batteries are far safer, and easier to recycle, and weight is no issue for stationary applications. That should be illegal. The only advantage of lithium packs is the weight for mobile / portable applications.

[Refugee]

The robot did not make it into active service before the lithium syndrome set in and cooked the battery off.
The planes had managed to get through type approval and had begun to carry passengers before the batteries started to suffer with explosive disassembly syndrome (EDS).
Just imagine the airport announcement that says the plane has got a flat battery. It would be correct if you look at the battery spread all over the inside of the aircraft as a thin flat layer of soot.

[Nick]

The planes had managed to get through type approval and had begun to carry passengers before the batteries started to suffer with explosive disassembly syndrome (EDS)

Being fair, the batteries in the 787 did NOT suffer "explosive disassembly" - they overheated and spread soot around the place, but did not explode or lose containment - the battery packs, whilst damaged, did not rupture though individual cells within the pack did.

OTOH, RoboSimian most certainly did explode.

[Refugee]

The smallest items known to suffer with explosive disassembly is E-cigs. I charge these with a strict 500ma limit.
Idiots plug the things into 2.1 amp chargers that are built into power sockets with no idea if the sockets have even got type approval or not.
E-cigs are plastered with fake CE marks and mitigation has to take place externally and that is the end if it.
With type approved things like smart phones suffering with explosive disassembly syndrome the things must all be charged in a steel box without exception.
In the 787 the battery box was indeed made of steel but it still did buckle a bit as can be seen in the photo in post #2.

[davegsm82]

I had an iPod Nano which went into EDS, fortunately it was on my workbench and not on the sofa, however it still sent shards of burning carbon-like material all over the room. Apple still have a replacement program in place that gives you a brand new iPod in exchange free of charge.

From what I understand, the 787 Li-ion problem was solved initially by retrofitting Lead-acid batteries and then returning to Li-ion but with greatly expanded ventilation to the outside of the plane from the sealed battery containment area which could handle an 'event'.

[Refugee]

They certainly did have to do something serious about those air craft batteries.

I have been looking at camera batteries.
These are either very expensive but not so much so that it becomes cheaper to buy two cameras to get an extra battery or or else they are at risk of EDS.
Power tools are now so cheap that a second one costs less than an extra battery for the first one. You just chuck two in the basket.

I am working on a way of safely charging dodgy Li-Iron batteries and will start a new thread when I have sorted it out with or without the fireworks.
Testing so far has come up with a dodgy battery that charged without exploding a few times before it began to de-laminate internally causing it to bulge and become difficult to insert into the device.

[Nick]

I am working on a way of safely charging dodgy Li-Iron batteries and will start a new thread when I have sorted it out with or without the fireworks.
Testing so far has come up with a dodgy battery that charged without exploding a few times before it began to de-laminate internally causing it to bulge and become difficult to insert into the device.

The chemistry of Lithium-based batteries is complex and quick to anger - really, you should not under any circumstances attempt to resurrect suspect units - it's just dangerous - a false economy.

As the charging profile is complex, subtle (must be exact), dangerous (if you get it wrong) and generally requires load-balancing at a cell level and sensor feedback, e.g. thermistors buried in the pile, several of the standard chip manufacturers produce ranges of cheap ICs that do all this for you. Phone batteries have exactly this - they are not just a LiPo stack.

e.g. Maxim make over 70 different charger ICs, some of which are universal, i.e. chemistry-independent. 

https://para.maximintegrated.com/en/sear...=batt_chrg

...also Linear Technology: http://www.linear.com/products/Linear_Battery_Chargers

One huge plus for the Linear Technology devices is that they provide full Spice models and examples for LTspiceIV - you can model the behavior of your design for free. I'm a big fan of LTspice and use it as my Spice of choice, as do 100s of 1000s of other engineers. And it's free

The App Notes for these chips are very good - I have used Maxim power management ICs in several designs - other manufacturers also have similar.

Whilst the appeal of doing this yourself may be great, I would encourage you not to - there is a lot of wrong and plain bad information on the www - and what works for you (some or even most of the time) may well cause a fire for someone else.