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Lithium Batteries can Explode Unexpectedly

No early detection was feasible... until now

Billions of lithium batteries are produced each year. The amount is growing 15% annually. 

They are used to power most electronic devices but with their high energy they are still not safe enough.

This clip shows a 10 Ah pouch cell exploding in a thermal runaway event caused by over-charging. The test was done under our funded  NYSERDA project #138128 at DNV-GL, Rochester, New York in August 2020. The project is coordinated by Actsys Inc.. This clip starts at an advanced stage of the test after the cell has begun to swell.


  • Widespread: Billions of people come into close contact with lithium battery-powered devices around the world every day. You place mobile phones in your pocket and next to your face, a laptop on your knees, sit on them in your EV or e-bike, charge them next to your bed at night, and some put them in their mouth as an e-cigarette or vape device.

  • Powerful: For example, the energy of the battery that an e-bike rider sits on is equivalent to about 1 kg of gunpowder. In some EVs it is about 100x more.

  • Frequent: A report from the US Consumer Safety Commission reported over 25,000 fire or overheating incidents of lithium batteries in a range of products over a 5 year period just in the US. According to FAA and EASA reports there has been a 10x increase in the number of lithium battery fires on aircraft and in airports the last few years. The London Fire Brigade reports more than 100 battery fires a month just in their city. In 2019 2% of the electric grid lithium energy storage systems in Korea caught fire due to battery failures.  And these are just a few of the alarming statistics.

  • Expensive:  For example, the reported losses to Samsung  because of their Galaxy Note 7 battery fire fiasco cost them a reported $17 billion.  According to  industrial sources, fires from charging e-bikes in residential buildings can result in $1M of damages per event.

  • Deadly: According to published studies there are close to 1,000 vape pen and e-cigarette battery explosions a year in the  US alone, some of which result in death. Lithium battery  fires on board cargo planes have caused crashes with loss of crew life.

Do you know the state of risk of your lithium battery?


  • Starts small:  Defects that cause thermal runaway may be caused by: manufacturing defects in the cell, discharging at high rates to supply current to power hungry applications, the stress caused by fast charging, and over-charging. Actually many types of unintended abuse like dropping a device or sitting on it can also initiate safety problems.

  • Easily initiated: The most common cause of thermal runaway in cells is an internal short circuit. Shorting may be caused under some charging conditions when sharp whiskers, called dendrites, of lithium metal penetrate the separator to bridge between the electrodes. The flow of current through the short generates heat which decomposes the flammable electrolyte and releases oxygen from the cathode to form an explosive mixture ignited by the generated heat. A short can also occur due to a tear in the separator, metal impurities introduced during production, or contact between electrodes which become misaligned during use or in manufacturing.

  • Hidden threat: The development of the defect leading to a short before it causes thermal runaway can take weeks without significantly affecting the performance of the cell. Detecting these early precursors especially in their benign early stage of development is very difficult.

  • Growing risk: 20 years after their major commercialization lithium ion batteries are becoming more hazardous. Their energy has doubled but they are now being made with less expensive materials and stressed more by faster charging and higher power uses. This promotes the creation of shorts.

  • Old Solutions: Conventional methods detect the hazardous defects when they have already begun to induce irreversible failure in the cell, near the threshold to thermal runaway. At this point it is too late to prevent an explosion. Also, these methods are expensive, have low sensitivity and measure a single parameter which lowers their reliability. In short, they cost a lot and are too little and too late to stop thermal runaway.

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