Even though it is an integral part of a rechargeable batteries construction for proper operation, could eliminating the anode improve current rechargeable batteries performance by leaps and bounds?
By: Ringo Bones
Though not quite anode-less yet but a rechargeable battery manufacturing company called Solid Energy Systems is currently developing a nearly anode-less lithium ion rechargeable battery and has recently exhibited a working prototype during the 2015 Mobile World Congress in Barcelona, Spain. Given the already widespread acceptance of the lithium ion rechargeable battery in mobile phone and hybrid / electric vehicle applications, Solid Energy System’s concept takes the strengths of the current technology much further by reducing the space taken up by the anode since it takes up most of the space in current lithium ion rechargeable battery configuration.
Solid Energy System’s nearly anode-less rechargeable battery concept could last twice as long as current lithium ion rechargeable batteries, while offering a 1,200 watt-hour per liter energy density. Designed with an ultra-thin metal anode, this configuration improves the cell-level energy density by 50-percent over current designs using graphite anodes and 30-percent improvement over silicon-composite anodes. Once marketed and used on current mobile devices, it could make them operate twice as long between recharging times.
According to Solid Energy Systems, the “secret” in boosting energy storage lies in swapping the conventional electrode material – graphite – for a thin sheet of lithium metal foil, which can store more lithium ions. Other battery manufacturers have been trying to use lithium-metal electrodes in rechargeable lithium ion batteries for decades with only a limited success. Solid Energy seems to have solved a couple of key problems which have caused such batteries to either stop working after a few charges or burst into flames. Current carbon anode cell energy density is at 600 watt-hour per liter while silicon anode cells offer energy densities of around 800 watt-hour per liter, while Solid Energy Systems’ near anode-less cell offer energy densities of around 1,200 watt-hour per liter.
Solid Energy Systems’ solution to make nearly anode-less rechargeable batteries to be as reliable as current lithium ion rechargeable cells without dying only a few recharge cycles or suddenly bursting to flames is via the use of both solid electrolyte and a liquid one. The solid electrolyte is applied to the lithium-metal foil, the ions don’t have to travel through this thin material, so it doesn’t matter that they are moving relatively slowly.
Solid Energy Systems’ prototype nearly anode-less battery can be recharged 300 times while retaining 80 percent of its original storage capacity – closer to what you would need in portable electronics. It also works at room temperatures whereas competing lithium-metal battery prototypes operate at temperatures too hot to be practical. As of late, most other companies investing in Solid Energy Systems’ newfangled batteries to become an economically viable commercial product are electric car / hybrid car companies with plans to use the newfangled rechargeable battery design in their electric cars.