The most efficient way to store renewable electricity is with rechargeable batteries. They’re needed to power electric cars, drones, light aircraft, and, increasingly, larger vehicles and store electricity on micro and larger electricity grids in the short term to ensure grid stability.
Lithium-ion batteries (LIBs) are the most viable short-term battery technology for these applications currently. However, for decarbonizing electricity grids, transportation, and much power in the digital world, more powerful, longer-lasting, faster-charging batteries will continue to be critical.
The further development of lithium-ion batteries will be important in the short term, fulfilling many of the roles that need batteries. Several inherent challenges continue to drive the development of new battery chemistries to complement existing LIBs and allow growth in different market segments.
Those high-level challenges to the implementation of batteries are as follows:
1. Cost
The cost of an electric car with a reasonable range is still too expensive for many consumers, even though the cost of EV batteries has decreased. While the cost of utility-scale batteries has decreased globally, they are still too expensive to compete with alternatives such as gas turbines or chemical electricity storage using hydrogen or ammonia.
However, short-term grid support, such as voltage and frequency regulation, plays a critical role. Furthermore, the cost of LIBs has dropped so dramatically that there is often little financial incentive to develop newer battery technologies like redox flow or sodium-ion batteries. While they are currently more expensive, partly because they are not mass-produced, they have the potential to become less expensive and more sustainable over time.
2. Energy density
Even though LIBs’ energy density has more than doubled since their invention, it is still insufficient to allow them to be used in heavy vehicles and airplanes. Gravimetric energy density is less important in grid-scale batteries. Cost, low volumetric energy density compared to compressed hydrogen or ammonia, and resource implications associated with the large sizes of batteries needed for large-scale electricity storage on the grid are still barriers to battery use. They will, however, continue to be used for ancillary services and as the primary storage for microgrids.
3. Longevity
It’s critical to extend the life of batteries and keep track of their health, which entails keeping track of their cost, sustainability, safety, and second-hand use. For the adoption of electric vehicles to continue, battery durability is a must. Many vehicle original equipment manufacturers (OEMs) provide warranties on electric vehicle battery packs that cover replacement if capacity drops below a certain threshold. This poses engineering difficulties.
Lithium-ion is still developing and hasn’t reached its full potential. Longevity and safety have significantly improved, while capacity has gradually increased. The goal of current research is to extend the life of cycles and calendars. Both are determined by the gradual degradation of components, particularly the cathode, anode, and electrolyte.
4. Scalability
LIB batteries are made up of small cells to form larger battery packs. The ions responsible for delivering energy inside the cells are only 0.2 nanometres in size. They move in and out of micron-sized particles (one-seventh of the thickness of a hair). If processes that work on such small scales are to be useful, they must be scaled up using increasingly efficient and automated manufacturing processes to operate in increasingly larger cells and battery packs – with scales and footprints measured in hectares.
5. Sustainability
Finite raw materials, the carbon footprint of manufacturing, the working conditions of their miners, and limits on reuse and recyclability are some of the examples of sustainability challenges in battery implementation. Batteries made from recycled components assembled in zero-carbon manufacturing processes are the ultimate net-zero goal.
6. Fast charging
Higher charging speeds encourage the adoption of electric vehicles by allowing drivers to overcome their ‘range anxiety.’ While many new electric vehicles can now travel up to 200 miles on a single charge, the fastest current technologies can only charge a car to 80% in 20-40 minutes. Better electrode designs and possibly new materials are required to allow safer, faster charging without reducing lifetimes. It also necessitates a significant investment in charging infrastructure.
7. Technology transfer
From discovery to deployment, innovations have taken anywhere from seven to ten years (or more); for example, LIBs took around 20 years to reach commercialization in 1991. Furthermore, as is typical of emerging technologies, regulatory policy lags behind current energy storage technology. Retail and wholesale market rules will need to be updated as residential, commercial, and industrial interest grows.
