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This car caused a garage fire in a nearby town today:
Anyone recognise what it could have been?

Nope not a clue

Breaking for spares ??

To be nice, foolish

It's going to be nice when technology brings about a less volatile battery option.

EvolutionRevolution wrote: Anyone recognise what it could have been?

for many reasons : TRAXXAS!

What size solar panel needed for 1/10

1/8th scale with pillow ball suspension..but nope, no clue

My god. That's too bad lipos are so sensitive. That really prevents me from switching to them. I enjoy my nicd batteries: roughly 30 years old, many times overcharged, no need to balance, took much heat in my parents' attic for more than 25 years and they work absolutely fine. No smoke, no fire...

Safety starts with a technology that doesn't turn into an inferno when using conditions are less than perfect.

Just put it on eBay with the disclaimer, "Due to the nature of the hobby..."

if you have experience with charging NiCD and NiMH batteries from the past, you are well aware of the dangers of changing methods, zapping/burping/peak, etc.

Lipo problems occur when guys are either discharging too far, or trying to hit the pack with too high a charge rate, or otherwise abusing a damaged pack or cell. If you get a pack with large capacity, run for a reasonable amount of time, and don't charge above the max C rating(or max charge rate recommended), they work very well. Lipo chargers have a bunch of features that makes it simplified. When not using them, place the charger in storage mode and it will set the pack to a safe range.

use a lipo vault or bag in the off chance something should go awry and you would be OK.

Same here... the only two lipos I've ever seen catch fire in racing conditions either did because
1) the racer forgot to switch the charging mode from NiXX to LiXX when he raced electric for the first time in the winter after the IC season was over, or
2) the center UJ pin of a Dex410 came lose because it hadn't been secured properly and tore through the case of the (saddle) pack while running

In both cases, this is human error... But for sure a fireproof bag doesn't hurt and they shouldn't be charged in the car. Strictly forbidden by most racing bodies btw...

If one think LiXX are dangerous for one's own good, then that person shouldn't be playing with a soldering iron or a dremel either... And one has probably forgotten what a SubC pack charged at 10A sounded and looked like when the delta-peak didn't work properly (hint: it's loud and there are metal shrapnels everywhere including in your face and eyes, and it goes INSTANTLY, no (hearable) warnings...)

Net: lipos don't kill people, people do.

My guess as to the cause of this, would be an incompetent user, coupled with an intolerant technology and poor engineering and quality control of the power system. That being said, from my R/C Li-Poly flying experience, even when using the best cells (korea made), the best charging equipment ( German, US, Korea or Japan), and best practice ( use, care, storage etc), the Li-Poly battery configuration is still touchy. To make the darn things reliable for long periods of time you can only use about the middle third of the voltage range, since anything at either extreme of the usable voltage range leads to grid oxidation. Of course this reduces the battery capacity, and you end up with about the same power density as a Ni-Cd. Oh, and in 17 years of flying Li-Poly, I have had 2 fires. Both when the batteries were stored at storage voltage, and neither had any physical damage. One was a year old, and other 2. One was a 2s170 mAh, the other 6s5000mAh. Both times the cells were stored in steel boxes half full of sand. My kids use Ni-Cd for that reason

makoman1860 wrote: ↑Mon Mar 12, 2018 12:20 pm My guess as to the cause of this, would be an incompetent user, coupled with an intolerant technology and poor engineering and quality control of the power system. That being said, from my R/C Li-Poly flying experience, even when using the best cells (korea made), the best charging equipment ( German, US, Korea or Japan), and best practice ( use, care, storage etc), the Li-Poly battery configuration is still touchy. To make the darn things reliable for long periods of time you can only use about the middle third of the voltage range, since anything at either extreme of the usable voltage range leads to grid oxidation. Of course this reduces the battery capacity, and you end up with about the same power density as a Ni-Cd. Oh, and in 17 years of flying Li-Poly, I have had 2 fires. Both when the batteries were stored at storage voltage, and neither had any physical damage. One was a year old, and other 2. One was a 2s170 mAh, the other 6s5000mAh. Both times the cells were stored in steel boxes half full of sand. My kids use Ni-Cd for that reason

Ha - Flying. This is a fair point.

Flying is really hard on cells (current draw in 3D heli is insane) and cells are over-stressed. So, yes, they can suddenly wake up in the ammo box and do funny things...

Cars are much softer on batteries, especially 10th scale. As long as your kids don't tinker with chargers, don't use bullet connectors, and you have lo-Voltage cutoffs on their cars you should be safe

8th scale is a different category, and large-scale is a totally different ball-game further down the line. The issue is the traxxas speed-crazed fanbois that runs cells of crap quality in high-current, heavy load configurations...

The issue with Lipos and BL in general is that they've made insane power available to the (unsuspecting) crowds. Once in a while this stuff happens. I'm curious to know how exactly Gil Losi got his stuff wrong...

Lonestar wrote: ↑Mon Mar 12, 2018 12:37 pm

makoman1860 wrote: ↑Mon Mar 12, 2018 12:20 pm My guess as to the cause of this, would be an incompetent user, coupled with an intolerant technology and poor engineering and quality control of the power system. That being said, from my R/C Li-Poly flying experience, even when using the best cells (korea made), the best charging equipment ( German, US, Korea or Japan), and best practice ( use, care, storage etc), the Li-Poly battery configuration is still touchy. To make the darn things reliable for long periods of time you can only use about the middle third of the voltage range, since anything at either extreme of the usable voltage range leads to grid oxidation. Of course this reduces the battery capacity, and you end up with about the same power density as a Ni-Cd. Oh, and in 17 years of flying Li-Poly, I have had 2 fires. Both when the batteries were stored at storage voltage, and neither had any physical damage. One was a year old, and other 2. One was a 2s170 mAh, the other 6s5000mAh. Both times the cells were stored in steel boxes half full of sand. My kids use Ni-Cd for that reason

Ha - Flying. This is a fair point.

Flying is really hard on cells (current draw in 3D heli is insane) and cells are over-stressed. So, yes, they can suddenly wake up in the ammo box and do funny things...

Cars are much softer on batteries, especially 10th scale. As long as your kids don't tinker with chargers, don't use bullet connectors, and you have lo-Voltage cutoffs on their cars you should be safe

8th scale is a different category, and large-scale is a totally different ball-game further down the line. The issue is the traxxas speed-crazed fanbois that runs cells of crap quality in high-current, heavy load configurations...

The issue with Lipos and BL in general is that they've made insane power available to the (unsuspecting) crowds. Once in a while this stuff happens. I'm curious to know how exactly Gil Losi got his stuff wrong...

Ha I like your last line, except I am usually less kind in my wording. As a general statement, as you take something that used to be so difficult or technical that is was only for those vested in it, and make it available to the average idiot, you are going to see problems. We didn't have nearly the issue with drones flying in controlled airspace before it was made easy enough for the average moron to fly one. As for my flight cells, I fly neither heli nor 3D electric, and the cells I had issue with were treated quite gently. From an industrial user standpoint there is no question that Li-Poly is one of the most unstable battery technologies. A Ni-cd used within the manufacturers instructions enjoys high levels of safety margin. The same cannot be said of Li-Poly. If we are building a pack for something mission critical and it is to be of Li-Ion 18650 cells, we will do a laundry list of tests to each cell, both mechanical and electrical before they are allowed to go in a pack. Nanosats up until about 2010 were all Ni-cd using off the shelf sanyo cells, then the switch was made to Sony 18650 Li-Ion cells and they have served well although there was a learning curve. There have been recent attempts at Li-Poly however the biggest obstacle seems to be mechanical, meaning vibration leading to internal damage. I suspect many of our hobby failures are for similar reasons.