Canadian chemists devise method to protect lithium metal anodes from corrosion and prevent fires and explosions
Using metallic lithium as the negative electrode in a battery has the potential to boost the battery’s performance by increasing the amount of charge it can store.
The team, based at the University of Waterloo in Ontario Province, has devised a method to get around two problems that have, until now, held back the development of metallic lithium batteries; corrosion of the electrode, which reduces the battery life, and development if microscopic whiskers of metal called dendrites caused by repeated charge-discharge cycles, which can lead to the risk of fires and explosions.
In a paper published in the journal Joule, the team explains that adding a phosphous sulphide (P2S5) to the battery’s electrolyte creates a thin film of a glassy protective compound, lithium sulphide (Li2S6) on the electrode which prevents both phenomena. This happens spontaneously inside an already-assembled cell, they add.
“We wanted a simple, scalable way to protect the lithium metal,” said team leader Quanquan Pang, who completed his PhD at Waterloo and is now a postdoc at MIT. “With this solution, we just add the compound and it works by itself.”
The increased energy density of the cells compared with standard lithium ion technology would increase typical electric vehicle range from some 200km on a single charge to around 600km, the team claims.
Improvements in battery technology are welcome, however range anxiety is stil caused by a lack of accessible charging points and the time to recharge!
There are some fundamental problems with the electric vehicles initiatives that seem to have captivated media and the politicians. If the bench mark is the Musk car with a battery of 200kwhr and it arrives at a service station half charged and requires topping off on a supercharge in 30 minutes that is 200kw of juice per car. 50 cars doing this simultaneously requires a 10MW grid connection. For 20 trucks with 1600kwhr batteries also arriving half charged and requiring to be fully charged in 30 minutes would require 16MW. A total supercharge peak demand of say 30MW at each service station and with 1000 service stations nationally would add 30GW onto the system at peak times. The infrastructure implications are “significant” . A power plant at each location possibly? Wind? Solar and other intermittent sources. Any general increase in electricity tariffs to pay for this sort of investment (+/- local power generation) would be inequitable and unfair for those not owning electric vehicles.
The best business proposition would be in the endless supply of coffee, doughnuts and reading material at the charging points. A road tanker with liquid fuel can fill up > 1000 cars. Makes you think!
Apart from the increased demand for high power hubs for charging on major trunk routes has any one considered the demands on the the electrical distribution system. It will require a total up grade in many remote areas, such as Cornwall to cater with the peak demands over the summer.
The power handling density in a lorry charging area will be similar to that in a steel mill or paper mill.
Internal Combustion is finished. Get over it and start planning on the service station infrastructure and Engineering opportunities of the (near) future!
Whether we need power stations at service stations we’ll find out as the tech progresses but most EVs charge up at home/destination so don’t require charging en route and if a Tesla has 100kWh still available I don’t think it should be asking for a top up as even something as power hungry as a Tesla will do 3 to 4 hundred miles on 100kWh so maybe the pump will just say “on yer bike”.
As a nation we have three times the generating capacity than we use between midnight and 6 am, the art of getting people to use this potential in their ev’s can be done by pricing alone, offering these units at a price of say 3p per unit as opposed to 30p a unit a 5pm should push the load to the excess capacity but not denying the chance of the unlucky or inept the chance of a get you home charge if needed. Another hole in the not enough capacity argument is when you run low on fuel near a highly priced middle of nowhere petrol station people have usually mastered the art of buying just enough to get home and not filling up totally.
What you seem to be suggesting is an unregulated electricity market where the distributer can charge whatever they want whenever they want. We all know what happens when there is a petrol shortage – price rises and panic buying!
With present storage capacity an electric vehicle cannot compete with the i c engine on range. In all other respects the electric vehicle is way superior. Constant motion machines will always be superior.
However, if one merely gazes at the volume of vehicles per hour at a motorway service area it is obvious that a large substation will be required on site. This will require a high voltage underground cable connection, none of this will be cheap.