There is a growing problem with lithium-ion batteries catching fire and even exploding on planes.
But what happens if this happens in space?
Turns out lithium-ion batteries are often used for space flight and NASA has a plan if they were to ever catch fire.
According to The Verge technical online magazine lithium-ion batteries power everything from electric tools and spacesuits to satellites and planetary rovers.
They must be built to withstand the extreme temperatures of the space environment and they also have to be packaged so that they don’t harm any astronauts if they accidentally explode.
Lithium-ion is perhaps the most powerful battery type available, but it comes with a risk called thermal runaway — when defects or mishandling causes a battery to overheat and explode.
If a battery caught fire inside a pressurised capsule, such as the space station, the results could be devastating. Fire inside such an oxygen-rich environment would be explosive and catastrophic.
NASA has figured out ways to package lithium-ion batteries so that thermal runaway would not be a total tragedy on the International Space Station. Before they’re sent to space, these batteries are carefully produced with various materials and technologies, designed to prevent them from spewing heat, smoke and fire if they were to combust.
Thermal runaway can happen if a battery gets too hot so NASA does try to mitigate that risk. Also, to protect batteries from the extreme fluctuations of space, heaters are added throughout the battery’s cells to regulate their temperature.
Battery screening is also key for NASA to weed out any defects in cells that might cause thermal runaway. But all the screening in the world can’t catch every defect. Sometimes cells are manufactured with a latent flaw that only manifests over time in the battery as it’s charged up and discharged.
So when a battery is being used on a human spaceflight mission it must be packaged carefully to keep astronauts safe. Specifically, NASA wants to make sure that if one cell within a battery goes up in flames, it doesn’t spread to all the other hundreds of cells inside that same battery.
Steel tubes are put round the batteries in case they explode. The cells are separated by aluminium within the battery so if one goes up in flames, it’s not in direct contact with the other cells.
A chimney path is needed that will funnel all of the hot molten material and smoke out of the pack if it explodes but the flames will be doused so only smoke will escape a failing battery pack.
* When it comes to planes AvSax fire containment bags are now on board several major airlines worldwide and were deployed 27 times in 2017.
If an electronic device – and that includes e-cigarettes - starts to seriously overheat or emit smoke the cabin crew will pour at least two litres of water into an AvSax. It is imperative to first knock down the flames from the device using an on board halon fire extinguisher, then transfer the device into AvSax before it reignites. Additional water is then required. The water activates the polymer gel inside the bag causing it to expand around the device. Should the device keep on venting then the AvSax is tough enough to absorb the energy.
The AvSax cools the batteries in the device, reducing the likelihood of the battery igniting but if it does go into thermal runaway it is all contained within the bag.
Amazingly, the water is absorbed into the internal lining of the bag so the device is dry when it is removed.