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Hi all. After reading a few dangerous and ridiculously lucky stories of people using various lithium cells, I decided to give some info as for some precaution and care for your batteries.
As most laser people know, batteries are primary or rechargeable. Most of us use rechargeable batteries. The most commonly used and discussed rechargeable batteries on LPF are Lithium-Ion for the great majority. I will be discussing a few facts, precautions and dangers of these lithium cells.
COMPOSITION
I should note what makes up a lithium cell, as adjusting any part of the chemical makeup of the cell drastically alters its charge and discharge performance.
The anode of the cell is made typically from graphite. This does not react with a whole load of stuff in the cell, so you should be fine here. The cathode differs in that it is made from either a layered oxide, a polyanion, or a spinel.
Lastly the most dangerous and critical part of the cell is the electrolyte.
The electrolyte is composed of organic carbonates, and vary from each cell, but they all do contain a lithium complex of some sort that IS the lithium in the cell.
DANGERS
As for lithium, it is a highly reactive metal, it tarnishes in air, and when burned, they release a MASSIVE amount of energy, reacting with the air and causing chemical reactions extremely quickly. If the lithium is exposed to high temperatures it will react FURIOUSLY, and burn most if not everything in its path. However, the lithium is placed in a molecular complex so it is less reactive however.
One big thing is that since most companies do not reveal their chemical composition, some lithium cells contain certain organic carbonates that have a LOW FLASH POINT. For those of you who play with fire, you should know what this is. Flash point is the temperature in which something gains the capability to explode. Combine that with the already unstable nature of lithium and you get something like this.
http://laserpointerforums.com/f53/beware-arctic-battery-explosion-54974.html
Regardless, due to a probable error in chemical composition, this happened. Lithium cells are extremely sensitive to changes in its composition, surroundings, and temperature. Also note that they are very fragile in terms of electric circuits.
I'd like to make this CLEAR. When dealing with li-ion cells under unprotected high-current draw, ALWAYS keep the cell's temperature below 90 deg F. This is the flash point of certain compounds in the cell. Always USE PROTECTION on your cells whenever possible. DX sells protection circuits for various batteries too.
PRECAUTIONS
If you want to lower the risk of a possible explosion or damage to you, property or to your supercool laser that you spent 350$ on... then
Check your Internal Resistance
Use a protection circuit
If possible, lower the current draw
Keep the Temperature low and cool
Do not dissassemble
Use responsibly
and keep an eye on them. They can be wild sometimes.
USE PROTECTION IN
Your eyes
Your surroundings
Your diode
Your driver
And lastly your cells.
I would like to lastly note that I am a chemistry major, so I can understand most of these terms. I simplified this for you guys.
Tell me if I have made an error, :thanks:
Iso
As most laser people know, batteries are primary or rechargeable. Most of us use rechargeable batteries. The most commonly used and discussed rechargeable batteries on LPF are Lithium-Ion for the great majority. I will be discussing a few facts, precautions and dangers of these lithium cells.
COMPOSITION
I should note what makes up a lithium cell, as adjusting any part of the chemical makeup of the cell drastically alters its charge and discharge performance.
The anode of the cell is made typically from graphite. This does not react with a whole load of stuff in the cell, so you should be fine here. The cathode differs in that it is made from either a layered oxide, a polyanion, or a spinel.
Lastly the most dangerous and critical part of the cell is the electrolyte.
The electrolyte is composed of organic carbonates, and vary from each cell, but they all do contain a lithium complex of some sort that IS the lithium in the cell.
DANGERS
As for lithium, it is a highly reactive metal, it tarnishes in air, and when burned, they release a MASSIVE amount of energy, reacting with the air and causing chemical reactions extremely quickly. If the lithium is exposed to high temperatures it will react FURIOUSLY, and burn most if not everything in its path. However, the lithium is placed in a molecular complex so it is less reactive however.
One big thing is that since most companies do not reveal their chemical composition, some lithium cells contain certain organic carbonates that have a LOW FLASH POINT. For those of you who play with fire, you should know what this is. Flash point is the temperature in which something gains the capability to explode. Combine that with the already unstable nature of lithium and you get something like this.
http://laserpointerforums.com/f53/beware-arctic-battery-explosion-54974.html
Regardless, due to a probable error in chemical composition, this happened. Lithium cells are extremely sensitive to changes in its composition, surroundings, and temperature. Also note that they are very fragile in terms of electric circuits.
I'd like to make this CLEAR. When dealing with li-ion cells under unprotected high-current draw, ALWAYS keep the cell's temperature below 90 deg F. This is the flash point of certain compounds in the cell. Always USE PROTECTION on your cells whenever possible. DX sells protection circuits for various batteries too.
PRECAUTIONS
If you want to lower the risk of a possible explosion or damage to you, property or to your supercool laser that you spent 350$ on... then
Check your Internal Resistance
Use a protection circuit
If possible, lower the current draw
Keep the Temperature low and cool
Do not dissassemble
Use responsibly
and keep an eye on them. They can be wild sometimes.
USE PROTECTION IN
Your eyes
Your surroundings
Your diode
Your driver
And lastly your cells.
I would like to lastly note that I am a chemistry major, so I can understand most of these terms. I simplified this for you guys.
Tell me if I have made an error, :thanks:
Iso
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