Lithium-ion batteries used in personal electronic devices including mobile phones and laptops are notorious for catching fire if damaged - and this is happening regularly on planes.
But researchers in the USA believe they have come up with a new design that won’t just stop the fire risk but the batteries will also hold more charge.
Lithium-ion batteries contain three main components: two charge-storing electrodes and a liquid organic electrolyte that separate them. The electrolyte ferries lithium ions back and forth between the electrodes during charging and discharging, but they’re flammable.
The research team led by Chunsheng Wang, a materials scientist at the University of Maryland in Baltimore near Washington, believe they have solved the problem by using a salt-rich water-based electrolyte which forms a protective solid shield around the electrodes that prevent them from ripping apart water molecules in the electrolyte’s interior.
For more details on the science behind it go to https://www.sciencemag.org/news/2019/05/new-generation-lithium-ion-batteries-could-hold-more-charge-without-catching-fire
In 2016, Samsung recalled the Note 7 mobile phone after several reports of exploding and burning devices due to a battery defect – a move which made headlines worldwide.
The rise in lithium battery fires is posing a particular problem in the confined space of passenger aircraft which is why cabin crew now often include in the safety briefing a warning that if passengers lose their mobile phones down seats they should alert the staff and not try to retrieve it themselves. If they do, the phone could get crushed in the seat mechanism, sparking a thermal runaway fire.
When this happens one cell overheating in a battery can produce enough heat – up to 900°C (1652°F) – to cause adjacent cells to overheat. This can cause a lithium battery fire to flare repeatedly or even explode.
One way to tackle such incidents is to use an AvSax fire containment bag which can deal with fires in personal electronic devices and are now carried on aircraft operated by 65 airline companies across the world – including some of the biggest and best-known.
AvSax – which won the Queen’s Award for Enterprise in 2018 - has been used more than 30 times to deal with emergencies since the start of 2017.
More than 13,500 AvSax are now carried on aircraft worldwide. Deployment is so effective that extremely expensive diversions to alternate airports are avoided.