LG Chem has developed a new material that could eliminate the risk of thermal runaway in lithium-ion batteries. This breakthrough can improve the safety of electric vehicles (EVs), smartphones, and various other devices that rely on these types of batteries.
Thermal runaway is considered a major challenge for the industry. It is a chain reaction that can lead to fires and explosions in lithium-ion batteries.
“Thermal runaway occurs when the cathode and anode inside the battery unintentionally come into direct contact, causing a short circuit and generating heat. Within seconds, the temperature can rise to nearly 1,000°C (1,832°F),” said the company’s press release.
To address this, LG Chem has introduced a temperature-responsive material called Safety Reinforced Layer (SRL).
“The thermal runaway suppression material is expected to be effective in preventing fires by quickly blocking the reaction path at the early stages of overheating,” it said.
A temperature-responsive solution
LG Chem’s solution is a thin, temperature-responsive material called Safety Reinforced Layer (SRL). It’s incredibly thin, measuring just 1 micrometer – about one hundredth the thickness of a human hair. This layer is placed between the cathode and the current collector, an aluminum foil that conducts electricity within the battery.
SRL acts like a smart fuse. Under normal operating temperatures, it allows electricity to flow freely. However, if the battery’s temperature rises beyond a safe range, SRL reacts.
“When the battery’s temperature rises beyond the normal range, between 90°C and 130°C, the material reacts to the heat, altering its molecular structure and effectively suppressing the flow of current,” explained the research team. This effectively stops the thermal runaway process in its tracks.
Moreover, SRL quickly responds to any temperature changes.
“This thermal runaway suppression material is highly responsive to temperature, with its electrical resistance increasing by 5,000 ohms (Ω) for every 33.8°F (1°C) rise in temperature. The material’s maximum resistance is over 1,000 times higher than at normal temperatures,” highlighted the press release.
Furthermore, the material is reversible. Once the temperature drops, the resistance returns to normal, allowing the battery to function as usual
Testing SRL’s Effectiveness
To demonstrate SRL’s effectiveness, LG Chem conducted extensive tests. In nail penetration tests on mobile lithium cobalt oxide (LCO) batteries, none of the batteries equipped with SRL caught fire.
This is a stark contrast to standard batteries, where only 16% remained fire-free in the same test.
In impact tests, where a 22 pound (10 kilogram) weight was dropped onto nickel cobalt manganese (NCM) batteries for EVs, all standard batteries ignited, but 70% of those with SRL did not, and even the 30% that did catch fire only had brief flames that went out quickly.
“Impact testing on 3.4-Ah pouch cells shows that the SRL reduces battery explosions from 63% to 10%,” LG Chem researchers reported in their paper.
Collaboration and development
The development of SRL is the result of a collaborative effort between LG Chem’s Platform Technology R&D team and Professor Lee Minah’s team from the Department of Battery Engineering at POSTECH. LG Energy Solution, LG Chem’s battery storage arm, also partnered in the safety verification process.
According to LG Chem, SRL overcomes the limitations of previous thermal runaway prevention methods, which often slowed reaction times or reduced battery energy density.
SRL can be readily integrated into existing mass production processes. The researchers have already demonstrated roll-to-roll production of SRL on current collectors at an impressive rate of 3 miles (5 kilometers) per day.
“This is a tangible research achievement that can be applied to mass production in a short period of time,” stated Lee Jong-Ku, CTO of LG Chem. “We will enhance safety technology to ensure customers can use electric vehicles with confidence and contribute to strengthening our competitiveness in the battery market.”
Lopsided_Quarter_931
I don’t like the term “explosion risk”. Thermal runaway isn’t the same as an explosion.
BagOk3379
Why can’t they just post what the thickness is using a standard unit? People are too dumb to understand units and need it compared to hair?
Spoiler: it’s 1 micrometer, which makes far more sense to me than “100x thinner than hair”, wtf
xstreamReddit
It’s basically a PTC material like previously used in some cylindrical cells but directly applied within the jelly roll. It will very likely decrease cell performance somewhat.
4 Comments
Extract:
LG Chem has developed a new material that could eliminate the risk of thermal runaway in lithium-ion batteries. This breakthrough can improve the safety of electric vehicles (EVs), smartphones, and various other devices that rely on these types of batteries.
Thermal runaway is considered a major challenge for the industry. It is a chain reaction that can lead to fires and explosions in lithium-ion batteries.
“Thermal runaway occurs when the cathode and anode inside the battery unintentionally come into direct contact, causing a short circuit and generating heat. Within seconds, the temperature can rise to nearly 1,000°C (1,832°F),” said the company’s press release.
To address this, LG Chem has introduced a temperature-responsive material called Safety Reinforced Layer (SRL).
“The thermal runaway suppression material is expected to be effective in preventing fires by quickly blocking the reaction path at the early stages of overheating,” it said.
A temperature-responsive solution
LG Chem’s solution is a thin, temperature-responsive material called Safety Reinforced Layer (SRL). It’s incredibly thin, measuring just 1 micrometer – about one hundredth the thickness of a human hair. This layer is placed between the cathode and the current collector, an aluminum foil that conducts electricity within the battery.
SRL acts like a smart fuse. Under normal operating temperatures, it allows electricity to flow freely. However, if the battery’s temperature rises beyond a safe range, SRL reacts.
“When the battery’s temperature rises beyond the normal range, between 90°C and 130°C, the material reacts to the heat, altering its molecular structure and effectively suppressing the flow of current,” explained the research team. This effectively stops the thermal runaway process in its tracks.
Moreover, SRL quickly responds to any temperature changes.
“This thermal runaway suppression material is highly responsive to temperature, with its electrical resistance increasing by 5,000 ohms (Ω) for every 33.8°F (1°C) rise in temperature. The material’s maximum resistance is over 1,000 times higher than at normal temperatures,” highlighted the press release.
Furthermore, the material is reversible. Once the temperature drops, the resistance returns to normal, allowing the battery to function as usual
Testing SRL’s Effectiveness
To demonstrate SRL’s effectiveness, LG Chem conducted extensive tests. In nail penetration tests on mobile lithium cobalt oxide (LCO) batteries, none of the batteries equipped with SRL caught fire.
This is a stark contrast to standard batteries, where only 16% remained fire-free in the same test.
In impact tests, where a 22 pound (10 kilogram) weight was dropped onto nickel cobalt manganese (NCM) batteries for EVs, all standard batteries ignited, but 70% of those with SRL did not, and even the 30% that did catch fire only had brief flames that went out quickly.
“Impact testing on 3.4-Ah pouch cells shows that the SRL reduces battery explosions from 63% to 10%,” LG Chem researchers reported in their paper.
Collaboration and development
The development of SRL is the result of a collaborative effort between LG Chem’s Platform Technology R&D team and Professor Lee Minah’s team from the Department of Battery Engineering at POSTECH. LG Energy Solution, LG Chem’s battery storage arm, also partnered in the safety verification process.
According to LG Chem, SRL overcomes the limitations of previous thermal runaway prevention methods, which often slowed reaction times or reduced battery energy density.
SRL can be readily integrated into existing mass production processes. The researchers have already demonstrated roll-to-roll production of SRL on current collectors at an impressive rate of 3 miles (5 kilometers) per day.
“This is a tangible research achievement that can be applied to mass production in a short period of time,” stated Lee Jong-Ku, CTO of LG Chem. “We will enhance safety technology to ensure customers can use electric vehicles with confidence and contribute to strengthening our competitiveness in the battery market.”
I don’t like the term “explosion risk”. Thermal runaway isn’t the same as an explosion.
Why can’t they just post what the thickness is using a standard unit? People are too dumb to understand units and need it compared to hair?
Spoiler: it’s 1 micrometer, which makes far more sense to me than “100x thinner than hair”, wtf
It’s basically a PTC material like previously used in some cylindrical cells but directly applied within the jelly roll. It will very likely decrease cell performance somewhat.