DenBarrettSAR
Enlightened
- Joined
- Sep 22, 2012
- Messages
- 260
- Ever wonder what it looks like when a Lithium Ion 18650 cell "vents" or goes into thermal-runaway inside a flashlight? Well we did just that during a controlled experiment as explained below.
- Back in June i traveled to Newfoundland, Canada to my home province for 3 weeks of traveling and off-grid camping. I brought along a ton of flashlights, some to do wilderness beam-shot photos, testing, etc.
Some plans that were set for this trip is to test the limits of 18650 Lithium Ion cells. as we will be doing some camping on my family's 80 acre land, there are some nice open gravel pits to do the planned testing. What i planned to do, is video record what happens when a Lithium Ion 18650 cell "vents" inside a flashlight, and outside a flashlight. I have a couple dozen of Laptop pulls, Ultrafire, and other worn out 18650 cells, and i will be doing a battery of tests on them in the gravel pit. Some of these tests will be Overcharging, over heating, short-circuiting, etc., both in and out of a flashlight. I have 4 – 5 aluminum flashlights i will sacrifice for these tests, most particularly for the over-charging/venting tests. I will also do remote-video testing of 18650 cells in a over-heating situation, by setting up a Propane torch to heat the cell to the point of explosion.
UPDATES: – July, 3,2016
we performed some LiIon 18650 cell testing to attempt to get them to vent. We used 50 ft of extension cord, and a wood block with two nails as contacts wired to the cord to hold the cell. ( these tests were not inside of a flashlight) On the other end upwind of the cell we applied 12 volts directly from a RV Deep Cycle battery, first positive polarity, then after 5 minutes with no venting, we reversed the polarity, then still no vent! one of the cells got so hot it began to melt the wrapper. I tested four different cells, a Sanyo, a Sony, a LG, and a cheap ultrafire. none of the cells vented with 12 volts from a large battery connected. then we decided to try 120 volt AC from a large inverter, still no venting!!!
they all got EXTREMELY hot, and one even arced the 14 gauge wire on the 18650 cell top to the point of welding the wire to the cell then melting the 14-guage copper wire away, but still did not vent!!! Later that day we will try heating the cell with a propane torch remotely to try to get them to vent...
UPDATE, July25,2016:
- Below is the photo of the flashlight damage, from a successful forced to vent its 18650 Li-Ion cell in the light.
>> The light was an all Aluminum side-clicky multi-5mm LED type. The light was turned on with a fully charged Samsung 18650 cell in the light, and force-vented from overheating to cause the thermal-runaway of the Lithium Ion 18650 cell. once i get the videos of the spectacular venting in action, i will post it here in another update. The force was great enough to cause the light to knock over the block of wood it was lend in place on by metal posts, along with a fireworks-like bang blowing out the side switch first, then blowing out the driver, lens, and LEDs board through the front. the head was intense enough to melt parts of the aluminum body, and disintegrate the driver board into ash in an instant.
Videos soon of both the in-light vent, and open cell venting of several cells, along with what it took to get these cells to vent, and what abuse they withstood!
- Back in June i traveled to Newfoundland, Canada to my home province for 3 weeks of traveling and off-grid camping. I brought along a ton of flashlights, some to do wilderness beam-shot photos, testing, etc.
Some plans that were set for this trip is to test the limits of 18650 Lithium Ion cells. as we will be doing some camping on my family's 80 acre land, there are some nice open gravel pits to do the planned testing. What i planned to do, is video record what happens when a Lithium Ion 18650 cell "vents" inside a flashlight, and outside a flashlight. I have a couple dozen of Laptop pulls, Ultrafire, and other worn out 18650 cells, and i will be doing a battery of tests on them in the gravel pit. Some of these tests will be Overcharging, over heating, short-circuiting, etc., both in and out of a flashlight. I have 4 – 5 aluminum flashlights i will sacrifice for these tests, most particularly for the over-charging/venting tests. I will also do remote-video testing of 18650 cells in a over-heating situation, by setting up a Propane torch to heat the cell to the point of explosion.
UPDATES: – July, 3,2016
we performed some LiIon 18650 cell testing to attempt to get them to vent. We used 50 ft of extension cord, and a wood block with two nails as contacts wired to the cord to hold the cell. ( these tests were not inside of a flashlight) On the other end upwind of the cell we applied 12 volts directly from a RV Deep Cycle battery, first positive polarity, then after 5 minutes with no venting, we reversed the polarity, then still no vent! one of the cells got so hot it began to melt the wrapper. I tested four different cells, a Sanyo, a Sony, a LG, and a cheap ultrafire. none of the cells vented with 12 volts from a large battery connected. then we decided to try 120 volt AC from a large inverter, still no venting!!!
they all got EXTREMELY hot, and one even arced the 14 gauge wire on the 18650 cell top to the point of welding the wire to the cell then melting the 14-guage copper wire away, but still did not vent!!! Later that day we will try heating the cell with a propane torch remotely to try to get them to vent...
UPDATE, July25,2016:
- Below is the photo of the flashlight damage, from a successful forced to vent its 18650 Li-Ion cell in the light.
>> The light was an all Aluminum side-clicky multi-5mm LED type. The light was turned on with a fully charged Samsung 18650 cell in the light, and force-vented from overheating to cause the thermal-runaway of the Lithium Ion 18650 cell. once i get the videos of the spectacular venting in action, i will post it here in another update. The force was great enough to cause the light to knock over the block of wood it was lend in place on by metal posts, along with a fireworks-like bang blowing out the side switch first, then blowing out the driver, lens, and LEDs board through the front. the head was intense enough to melt parts of the aluminum body, and disintegrate the driver board into ash in an instant.
Videos soon of both the in-light vent, and open cell venting of several cells, along with what it took to get these cells to vent, and what abuse they withstood!
