Time could be starting to run out for lithium-ion batteries as the race is on to design the next generation of batteries to replace them.

Lithium-ion rechargeable batteries first hit the market in the 1990s but the world’s supply of the metal lithium – now known as a tech metal – is limited. It is now mined mainly in Latin American countries including Argentina, Chile, Bolivia and Mexico before being shipped off usually to China to be transformed into batteries that can power anything from mobile phones to vehicles.

The environmental website China Dialogue reports that companies and consumers are constantly demanding batteries that are safer, last longer and pack more energy.

New uses for batteries are also rapidly emerging, including electric vehicles and grid storage, adding to the demand for better batteries. 

To meet these needs the race is on to develop the next generation of batteries, although what they will look like and how they will improve on current ones is still unknown.

To reveal the batteries shortcomings then we need to get technical for a moment.

China Dialogue puts this very clearly.

In its simplest terms, a battery is made up of a cathode, anode and an electrolyte. The negatively-charged electrons flow through the electrolyte from the negatively-charged anode to the positively-charged cathode. This flow of electrons is a current.

Cathodes are usually made out of a lithium metal oxide so batteries with this type of cathode are called lithium-ion batteries. These are the most popular kind because they most efficiently pack lots of energy into a small space like your mobile phone. When it comes to charging and discharging, lithium can provide three times the energy density of conventional rechargeable batteries.

Most lithium-ion batteries are made up of a graphite anode and liquid organic electrolyte. Inside the battery, the main barrier against short-circuiting is a thin and porous slip of polypropylene (a type of plastic) that stops the cathode and the anode from touching each other. If the separator breaks or erodes then the electrodes can come in contact and the battery will heat up extremely quickly. Batteries are filled with a flammable electrolyte which can combust when it heats up – something that can easily be triggered by a short circuit. And to cap it off, liquid electrolytes can also leak.

To overcome these problems researchers are investigating solid-state alternatives.

The new generation of batteries are highly likely to be still lithium-ion but will use different electrolytes. For example, they may have a solid-state electrolyte instead of liquid.

The requirements placed on an electrolyte are high. It must conduct electricity, withstand high voltages and remain electrochemically and thermally stable over a long period of time. This is why developing a solid-state alternative is so challenging.

Lithium sulphur batteries, which are based on a completely different chemistry, are another promising future battery. Theoretically, they can store a large charge and use sulphur, which is abundant.

Another alternative is sodium-ion batteries which work in a similar way to lithium-ion but use sodium instead which is again more readily available.

For more information go to https://www.chinadialogue.net/article/show/single/en/10808-The-race-to-develop-the-next-generation-battery

* More than 50 airline companies across the world – including some of the biggest and best-known - now carry AvSax fire containment bags to deal with fires in personal electronic devices caused by lithium-ion batteries that power them.

The bag – which won the Queen’s Award for Enterprise this year - has been used 27 times to deal with emergencies since the start of 2017.