Lost battery tab

[Nigel]

Agreed - the tabs struck me as not the best idea. Too bad they didn't, as an example, a cloth tab.

If a battery does get stuck from swelling, all I can think of is to run a small screw into slot of the tab and pull on the screw. Since a swollen battery is automatically no longer safe to use (*), I'm not too worried about the screw making a mess of things.

Putting a screw into a lithium battery is one of the best ways to make it ignite.

DO NOT POUR WATER ON A LITHIUM BATTERY FIRE!

While the battery is exploding, the fire is hot enough to disassociate the oxygen and hydrogen in water (water = H2O) which will make things exponentially worse. If the explosions are over, Halon or CO2, powder, or water can be used to put out the associated fire. If you think a battery might go, unless you have a Halon or CO2 extinguisher, let it go. BTW, Halon, being a fluorocarbon, can release fluorine gas when used in a very hot fire - fluorine gas is bad for all living things, including you.

Have a nice day.

The advice for lithium battery fires is normally to use water since it is the most effective way of removing the heat and preventing the fire from spreading, CO2 doesn't help much since the battery doesn't need external oxygen to burn and non of the gas extinguishers absorb much heat. The only exception would be for high voltage lithium batteries due to the risk of electrocution, not a problem for cameras.

Note that there is not much lithium in the battery that can be burned so it is not the same as a BMW engine fire where the best approach is to run since it is impossible to extinguish!

I've been carrying the Gitup F1 today in the cold winter weather, makes a lovely warm hand warmer when turned on! Never gets anywhere near hot despite using the same processor and not having a metal case to keep it cool.

 

[RBEmerson]

Water (assuming oil or gasoline isn't involved) or any other coolant works well, after the explosion. While the lithium is going off, very much a bad idea (disassociation). BTW the all-time winner for causing catastrophic failure is a short. Lots of power moving at once leads to enough heat to start the lithium component burning. The moral of the story: "don't be stupid and short the battery, sit on it, or poke it with something". Lots of pressure on the case (sitting on, squeezing, or jabbing a battery) shorts the battery internally. Deformation from overheating can do that, too. Oops!

 

[Nigel]

Water (assuming oil or gasoline isn't involved) or any other coolant works well, after the explosion. While the lithium is going off, very much a bad idea (disassociation). BTW the all-time winner for causing catastrophic failure is a short. Lots of power moving at once leads to enough heat to start the lithium component burning. The moral of the story: "don't be stupid and short the battery, sit on it, or poke it with something". Lots of pressure on the case (sitting on, squeezing, or jabbing a battery) shorts the battery internally. Deformation from overheating can do that, too. Oops!

Lithium batteries don't explode! They just burn fairly rapidly.

They also don't contain significant amounts of Lithium metal so the lithium does not burn, it is other things burning. Most of the Lithium in the battery is not in metal form in a Lithium-ion battery.

 

[RBEmerson]

Det cord, made with PETN and used for demolition, "only" burns at about 6400 m/s - 21,000 fps. Remember, too, if someone tosses water on the cell just before it goes poof, the hydrogen & oxygen separated by the heat from the cell will add their own mischief to the event. Exploding vs. burning very fast is a difference in search of a distinction.

(Trivia: there's a right way and a wrong way to tie branches of det cord to the main run. With the right way, the branch goes BOOM! too. Done the wrong way, the knot remains intact after the main run of det cord is detonated. It's a little weird to pick the branch and see the knot still there.)

 

[Nigel]

Det cord, made with PETN and used for demolition, "only" burns at about 6400 m/s - 21,000 fps. Remember, too, if someone tosses water on the cell just before it goes poof, the hydrogen & oxygen separated by the heat from the cell will add their own mischief to the event. Exploding vs. burning very fast is a difference in search of a distinction.

(Trivia: there's a right way and a wrong way to tie branches of det cord to the main run. With the right way, the branch goes BOOM! too. Done the wrong way, the knot remains intact after the main run of det cord is detonated. It's a little weird to pick the branch and see the knot still there.)

Det cord does not burn, it is made of explosive and it detonates (explodes).
Safety cord burns, it is made of gunpowder which burns, it is not an explosive. Two different processes.
Lithium batteries burn, not explode.

 

[Deleted member 24437]

Dont know about current ones, but the GP4 i think was also plagued by heat issues as i recall.

Sure metal can conduct heat, it cam also trap heat, if you want it conducted the best thing are to have the heat generator touching the metal to facilitate transfer of heat as optimal as possible.
But that just bring you half way there, the metal in turn have to offload that heat to something, in most cases air, and to do that optimal you will need a steady flow of air over the metal, and to further increase heat transfer you need as much surface area as possible.
This is why you see computer CPU coolers have a lot of fins to increase its surface area by a large factor, the pickup point from CPU to the cooler can be small but exchanging from heat in the metal of the cooler to air you need a larger surface area as its a less optimal to transfer heat into air.
This is why water cooled computers are a step up from air cooled, its the same rules in play but transferring heat into water are more easy, but you still need a radiator to transfer the heat of the water into air.
Again here whit water cooling you can go passive, but its way less effective so you will see much higher temperatures.

In general i find that with computers and say comparing a 2 fan ( 120 mm ) heat pipe cooler to a water cooled setup with a dual fan ( 120 mm ) on the radiator, you can in general get off with running the fans on the radiator at half the speed the fans need on a air cooler to get the same temperatures, and amping things up with overclocking the CPU mean the water cooled rig can go further up in CPU speed.

Off course you can go passive cooling on a computer CPU too, but you at least need a heat pipe cooler then, to use liquid / gas in the heat pipe to aid in heat transfer, and then you probably have to use a CPU that dont generate as much heat.

To my knowledge no action or dash cameras have the main heat generator ( the SOC ) directly in contact with the chassis, this might even be a bad idea as you will have a direct heat path so at least some point of the chassis could become almighty hot.

Iphonedo.com compared Heros5, 6, yi4k+ and Iphonex, he showed the 6 shutting down from overheat at 51 or 52 degrees C

 

[Deleted member 24437]

The

Dont know about current ones, but the GP4 i think was also plagued by heat issues as i recall.

Sure metal can conduct heat, it cam also trap heat, if you want it conducted the best thing are to have the heat generator touching the metal to facilitate transfer of heat as optimal as possible.
But that just bring you half way there, the metal in turn have to offload that heat to something, in most cases air, and to do that optimal you will need a steady flow of air over the metal, and to further increase heat transfer you need as much surface area as possible.
This is why you see computer CPU coolers have a lot of fins to increase its surface area by a large factor, the pickup point from CPU to the cooler can be small but exchanging from heat in the metal of the cooler to air you need a larger surface area as its a less optimal to transfer heat into air.
This is why water cooled computers are a step up from air cooled, its the same rules in play but transferring heat into water are more easy, but you still need a radiator to transfer the heat of the water into air.
Again here whit water cooling you can go passive, but its way less effective so you will see much higher temperatures.

In general i find that with computers and say comparing a 2 fan ( 120 mm ) heat pipe cooler to a water cooled setup with a dual fan ( 120 mm ) on the radiator, you can in general get off with running the fans on the radiator at half the speed the fans need on a air cooler to get the same temperatures, and amping things up with overclocking the CPU mean the water cooled rig can go further up in CPU speed.

Off course you can go passive cooling on a computer CPU too, but you at least need a heat pipe cooler then, to use liquid / gas in the heat pipe to aid in heat transfer, and then you probably have to use a CPU that dont generate as much heat.

To my knowledge no action or dash cameras have the main heat generator ( the SOC ) directly in contact with the chassis, this might even be a bad idea as you will have a direct heat path so at least some point of the chassis could become almighty hot.

The origional Yi cam has a 5/8 inch roughly square pce. of what looks heat transfer material above the SoC and in contact with the chassis!

 

[RBEmerson]

Det cord does not burn, it is made of explosive and it detonates (explodes).
Safety cord burns, it is made of gunpowder which burns, it is not an explosive. Two different processes.
Lithium batteries burn, not explode.

This discussion has, and I have some responsibility for this, drifted well off-topic for a forum concerned with the SJ7. It's time to move on.

 

[TonyCams]

This discussion has, and I have some responsibility for this, drifted well off-topic for a forum concerned with the SJ7. It's time to move on.

Yes, INDEED!

 

[Deleted member 24437]

Blabby!