You are the first to cry "corruption" here.
Tesla is significant only as a pioneer car, not as a brand. Because the battery-pack is thousands of times bigger than a e-skateboard or e-bike. Not to single-out Tesla... ALL the fuel-engine car/truck makers are switching over to battery ASAP. Even engine-crazed Honda (yes, we have 1st-generation Honda Insights still on the road here) and slow-to-change Cadillac. Even the Hawg: Harley-Davidson has paused their putt-putt factory to focus on e-hogs.
They can't all get top-class batteries, not at first. They will take what they can get and hope the accidental-death lawsuits don't pile-up.
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I remember having a look at RC batteries packs and chargers on Amazon and being fairly appalled by the casualness of it all.
Prototype packs in my world are stored in fireproof cabinets, and battery "Bat" boxes.
I think preventing the mischief in the first place is a better approach than protective wraps around the cells.
Tesla has a pretty good safety record with Li cells. They essentially bought out Panasonic's battery making operation and expanded it.
Demand for Li cells of all types is very high, the technology is evolving rapidly. Cells I designed with 4 years ago are largely obsolete already and have been replaced with improved versions The elimination of cobalt and nickel in newer cell types seems to have become a goal.
Energy densities are going to continue to increase and there are some improvements in electrode design and chemistry that are in the wings that will likely increase the capacity of typical cells by more than 50% in the next few years.
Recycling Li cells at actual end of life is a problem, people have not quite figured out how to quickly and safely disassemble cells for recycling. The economics of recycling require this. The materials themselves are very recyclable. Unlike other cell technologies they don't just die at the end of their primary service lives, and in many instances a number of additional years of service are possible in less demanding applications like power back up and load/generation balancing for the utilities. Hopefully by the time we have lots of near dead cells there will be an economical means to disassemble and process the materials for reuse.
The point here seems to be users are not trained.
Cell phones catching fire?
Yes, but with the wrong charger or batteries, rare these days as the battery is now inside in a difficult to swap location.
Charge controller is inside the phone. So some added safety.
Electric vehicles also have some sort of protection because of safety and life concerns.
The things catching fire are devices sourced from the cheapest supplier, and also with users using the wrong kind of chargers, too much current can cause the circuit to short closed, with terrible results.
That scooter was probably made with cheapest possible parts, sourced from Far East vendors, who will quite correctly say our battery worked, we did not expect it to be used thus...and the scooter maker will be hard to pin down, as the instructions are quite detailed.
All they will say is that our instructions were not followed.
So the owner, who left it to charge without being around, is to blame.
Just got a 18650 cell, 3.7V, 2000 mAh, 65 cents.
Will be used in a torch, the old one is in need of changing.
Probably R-C network, with bridge diodes to charge it.
Safety? Don't talk about it.
Cell phones catching fire?
Yes, but with the wrong charger or batteries, rare these days as the battery is now inside in a difficult to swap location.
Charge controller is inside the phone. So some added safety.
Electric vehicles also have some sort of protection because of safety and life concerns.
The things catching fire are devices sourced from the cheapest supplier, and also with users using the wrong kind of chargers, too much current can cause the circuit to short closed, with terrible results.
That scooter was probably made with cheapest possible parts, sourced from Far East vendors, who will quite correctly say our battery worked, we did not expect it to be used thus...and the scooter maker will be hard to pin down, as the instructions are quite detailed.
All they will say is that our instructions were not followed.
So the owner, who left it to charge without being around, is to blame.
Just got a 18650 cell, 3.7V, 2000 mAh, 65 cents.
Will be used in a torch, the old one is in need of changing.
Probably R-C network, with bridge diodes to charge it.
Safety? Don't talk about it.
We had dirt cheap chargers, RC network, bridge diode, and smoothing capacitor, 50 cents retail.
Sometimes the RC network would give mains to the phone, due to parts failure, destructive.
Not seen much nowadays, many chargers are available, all have more or less the same pin, and still cheap, but with Ferrites and SMPS design.
So mains isolated for the most part.
And many people have extra chargers, as their phones are replaced, or damaged. The RC designs are not seen now.
Sometimes the RC network would give mains to the phone, due to parts failure, destructive.
Not seen much nowadays, many chargers are available, all have more or less the same pin, and still cheap, but with Ferrites and SMPS design.
So mains isolated for the most part.
And many people have extra chargers, as their phones are replaced, or damaged. The RC designs are not seen now.
This would be a normal remark in a manual for equipment with NiMH batteries and a standard charger. For Li-ion, the charger itself should prevent overcharging.
What is it, 35 or 40 degrees Celsius maximum ambient temperature during charging?
Indoors?
Not in India, for the most part, here it goes well above that in summer.
Li-Ion, again the equipment itself is not as well made as it should have been.
Not in India, for the most part, here it goes well above that in summer.
Li-Ion, again the equipment itself is not as well made as it should have been.
I designed with Li-ion batteries for implantable hi-rel medical products like neurostimulators . My favourite batteries were made by SAFT, also deplyed in space mission. they had a mechnical safety contact when the gas pressure inside the battery can was too high , the current was turned off. we were not allowed to design as if we could use that feature, multiple overcharge protection mechanisms had to be in place, both in softwhere and hardware
Lady at yard sale gave me a Dyson hand held vacuum. $150 unit, by the receipt inside the manual, failed by fracture of a 1/8" thick plastic clip breaking off, which holds the bottom lid closed onto the dust catch basin. I asked her for the charger, she went inside and returned explaining she couldnt find it...
Bench supply for +/- 15V @ 1A, set to 21.7 across both rails, charging it. Blue light is supposed to go off when it's finished. After reading this thread, it sits out in the middle of the poured concrete driveway pad, not using the original Dyson charger...
Bench supply for +/- 15V @ 1A, set to 21.7 across both rails, charging it. Blue light is supposed to go off when it's finished. After reading this thread, it sits out in the middle of the poured concrete driveway pad, not using the original Dyson charger...
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The blue light, went out - after better than 5 hours with that as a DC source. I believe this indicates that the charger control circuit is in the unit and that the batteries took current for that long to charge, I'd guess they're in fairly good shape. Hopefully, we'll see tomorrow how long she lasts...
Dyson apparently designs their stuff better than the "hoverboard" people do; I could have left that linear power supply on overnight because when that blue light is off, it's no longer taking any current, so it's virtually disconnected from the source anyway. Short of a charging circuit malfunction, it should be pretty safe in that state. Identical to if I had Dyson's wall bug in place.
So the hazard of the batteries is up to the BMS circuit and it's a matter of how well that part of the "power delivery system" is designed. I find it irresponsible to sell a battery powered vehicle where the user cant walk away indefinitely once the charging process is begun. That's just such a "boy scout" design, which led to predictable disaster.
I hope the folks doing DIY of portable sound systems, powered by lithium batteries, are seeing this thread.
Dyson apparently designs their stuff better than the "hoverboard" people do; I could have left that linear power supply on overnight because when that blue light is off, it's no longer taking any current, so it's virtually disconnected from the source anyway. Short of a charging circuit malfunction, it should be pretty safe in that state. Identical to if I had Dyson's wall bug in place.
So the hazard of the batteries is up to the BMS circuit and it's a matter of how well that part of the "power delivery system" is designed. I find it irresponsible to sell a battery powered vehicle where the user cant walk away indefinitely once the charging process is begun. That's just such a "boy scout" design, which led to predictable disaster.
I hope the folks doing DIY of portable sound systems, powered by lithium batteries, are seeing this thread.
No, not "we all".....
I don't sleep with anything charging going on.
And I tossed my old cellphone years ago.
I sleep next to a charging phone and two charging watches.... Sometimes with a pair of headphones also charging. I also have two lead acid batteries float charging near my bed. Not worried about it but there's a fire cabinet outside of my door anyway.
Neuro stimulators?
Those need to be really reliable.
My mom had a Medtronics Activa PC system installed, Parkinson's DBS surgery done, then after it got depleted, changed to Scene-Ray from China.
Brain leads were not changed.
Better features. Bigger capacity battery, it is a modified Kinetra.
Those need to be really reliable.
My mom had a Medtronics Activa PC system installed, Parkinson's DBS surgery done, then after it got depleted, changed to Scene-Ray from China.
Brain leads were not changed.
Better features. Bigger capacity battery, it is a modified Kinetra.
Maybe the portable sound box boys should put a thermal fuse, common in electric irons?
For their own safety.
Also a fuse that is rated for max. discharge rate from battery.
For their own safety.
Also a fuse that is rated for max. discharge rate from battery.
I dabbled in the RC car world for awhile, and there is a wide range of attitudes. There is a lot of safety and best practice information available from battery manufacturers, vehicle manufacturers, and event organizers, etc. But a lot of people didn't pay much attention to it.
I always bought packs with a hard plastic case, but a lot of the more affordable brands sell packs wrapped in a heat shrink tube. Most fires happen while charging, but I suspect there was some damage in the first place that lead to the issue while charging. But at the same time, some cells just catch on fire for no apparent reason.
The vast majority of fires happen while charging or discharging. Rarely during storage.
Right around the time I quit I was seeing "high voltage" lithium cells starting to pop up. They claimed to be safe to charge to a higher voltage. I'm not sure they were actually different than regular cells. I think the marketing is giving people permission to push the limits. Of course battery life suffers, but the people who buy them know this already.
What is a little scary is that in race classes with strict motor and battery rules, people try to get an advantage by charging batteries at something silly like 100A. This damages the pack in the long run, but it also gives them a significant advantage over batteries charged at safe amperage. These guys race a battery maybe 10 times and then replace them.
Another scary thing is people who do not use balance chargers! They will say they balance charge like a good boy when they go home, but when they are using their vehicle, they do not balance charge because it takes longer. They say that a "good" pack will charge evenly, so there isn't any risk from not balance charging.
So yeah, some people are careful and do things safely, but a lot of people are careless or even reckless. And incidents are uncommon enough to lull people into false security. Or worse, a person who just doesn't know the requirements of lithium batters and does something tragically wrong like using a 12v battery charter on a lithium cell..
I am a retired automotive engineer, the company I worked for has had electric and hybrid vehicles since 2009. So I have 10 years of experience with lithium ion battery packs, I have tremendous respect for the dangers involved.
Yet I want to build a phono preamp powered by batteries, + - 12vdc rails. I am torn between having a quiet power supply and deeply concerned about charging batteries in my home. I have no interest in sitting watching batteries charge to make sure they don't overheat.
Yet I want to build a phono preamp powered by batteries, + - 12vdc rails. I am torn between having a quiet power supply and deeply concerned about charging batteries in my home. I have no interest in sitting watching batteries charge to make sure they don't overheat.
1. You don’t need lithium ion technology to power a preamp. SLA will work fine here. So what if it weighs a pound or two more.
2. You can buy a pre-engineered charging system for a battery, if you don’t trust your DIY efforts.
2. You can buy a pre-engineered charging system for a battery, if you don’t trust your DIY efforts.
I have rebuilt a few "no-brand" electric skateboard and electric bike battery packs made with 18650 cells, and they are quite scary inside, with complete disregard of safety standards. The BMS is a generic board with flimsy connections to the cells. Insulation is substandard; parts are kept in place with hot glue. On two istances, the thermistor was not inserted in the battery pack and could not have triggered the overtemperature protection when needeed. Manufacturer identification markings are missing and at least one of the packs I replaced seems to have been made with assorted reclaimed cells, disguised with a new plastic sleeve.
And........ here's one more you can add to the Lithium-Ion garbage can.
https://6abc.com/costco-umbrella-recall-sunvilla-solar-patio-umbrellas/11996553/
https://6abc.com/costco-umbrella-recall-sunvilla-solar-patio-umbrellas/11996553/