Recently, there was a post on Reddit, discussing the progress of EV batteries. While many focused on the currently ongoing research, there are many developments that are completed and in progress. Especially with Tesla being the EV leader, technological advancements are competing against Tesla’s technology.
Battery design roadmap
When looking at a product roadmap there will be a request to understand how the energy storage system will improve throughout the lifetime of the product. Sometimes these changes in technology can be very disruptive and very enabling at the same time.
Wh/kg is a key metric that we look at when comparing cells. Looking at production values and adding roadmaps gives you an interesting view of the future. All of this is underpinned by fundamental chemistry research, this fundamental research takes time to develop, understand and solve. One of the simplest ways is to increase the size of the cell. Increasing the Ah capacity means less overhead in terms of supporting material, and a lower number of parts in the manufacturing process. Hence lower cost. The downside can be the electrical and thermal performance of the cell. An example of this is the Tesla move from 18650 to 21700 to 46800.
Old electric batteries
The transition to EVs has been accelerated on both sides of the Atlantic, with a ban on the sale of new petrol and diesel cars in the UK by 2030, and a goal set for half of all new vehicle sales in the US to be electric by 2030. ‘Range anxiety’ has been recognized as a concern for potential EV drivers, with £950m ($1.16bn) of UK government funding now earmarked for rapid charging at service stations and £1.3bn ($1.59bn) for EV charging infrastructure, including homes and streets.
Similarly, the US has declared that there will be 500,000 EV charging stations nationwide by 2030. The White House has introduced a plan to distribute $5 billion (£4,091,000,000) to states across the nation3, which should help to eliminate range anxiety amongst drivers. The hundreds of gently topped-up cells inside an EV battery mean that each battery pack is expected to retain its charging-discharging capacity from 100,000 to 200,000 miles. Manufacturers are so confident of the battery’s road use that most electric cars come with an extended warranty of eight years or 100,000 miles.
Once an EV battery starts to lose its capacity to power a vehicle over distance, it still has useable life in it. When an electric car battery’s performance drops to 70% or less, its ‘second life’ revs into action. Aside from energy storage in your home or workplace, on a larger scale, former EV batteries can be used to power manufacturing plants and streets. In a virtuous energy cycle, eventually, the factories that produce the batteries could be powered using the repurposed batteries.