Batteries are systems. Getting the highest performance from Li-ion rechargeable batteries requires research and a sound understanding of each of the component parts of cells and the way they interact. Anode materials must be optimised to work in conjunction with conductive additives, electrolytes and binders.
Real world operating conditions are as important as theoretical parameters in delivering user benefits across challenging applications.
‘At Nexeon, we are fortunate to be working with some of the best carbon, electrolyte and binder companies in the industry.”
Dr Scott Brown, CEO
Lithium Ion: The Battery Technology of Choice
Lithium ion (Li-ion) rechargeable batteries will remain the technology of choice for the foreseeable future. Compared with other mature technologies, Li-ion offers the best combination of:
- Energy density (light weight, small volume)
- Low self-discharge (retains its charge when not in use)
- Established and low cost manufacturing
- Wide range of formats
Other battery technologies are in development, but none is yet ready to challenge the performance of lithium ion.
Today’s applications demand ever greater battery performance so lithium ion batteries need to work even harder … the future lies in better lithium ion cells.
Lithium Ion: The Anode and the Cathode
The lithium ions in a Li-ion cell move from the cathode to the anode as the cell is charged, and back again on discharge.
To achieve ever improving energy density, we need a cathode which contains more lithium and anodes which can absorb more lithium.
Nexeon is developing improved anode materials.
Next Generation Lithium Ion: Silicon Anodes
Traditional lithium ion batteries use graphite in the anode: a graphite-based battery in a smartphone stores enough energy to watch movies for about two hours.
Replacing the graphite with silicon will extend the viewing time significantly.
So, why don’t all lithium ion batteries already use silicon anodes instead of graphite? Current forms of silicon expand on charging – and an expanding battery would break the phone!
Nexeon has been working to overcome this expansion issue and is developing silicon anodes that:
- provide the high energy density benefits of silicon
- are engineered so that expansion is not a problem
- can be used in conventional battery manufacturing plants: same equipment, similar battery chemistry
- perform as well as graphite anodes in all other respects (high power rates, tolerant to temperature extremes etc)
- can be combined with graphite to produce silicon graphite composite anodes
Nexeon technology overview
Nexeon is a world leader in engineered silicon materials for battery applications. Nexeon has identified a class of material that the company believes will be one of the “best-in-class” in terms of energy density while maintaining physical anode dimensions for long cycle life.
Nexeon’s lithium ion battery anode technology uses silicon in several forms either to enhance or replace the traditional graphite anode. It can be used with graphite as a silicon graphite composite. The battery technology has the potential to improve the performance of the current Li-ion batteries used in electric vehicles and a wide range of consumer electronics.
Nexeon’s development of silicon materials enables the production of batteries with higher energy density. Nexeon has designed its technology for easy adoption in existing Li-ion battery production lines. Nexeon’s silicon materials can be used in combination with conventional polymer binders and current collectors as part of the standard battery manufacturing process. In this way, Nexeon technology truly offers a ‘drop-in’ approach.
Nexeon is developing two types of silicon material solution:
- Silicon based composite powder designed for use in hybrid or low loading anode electrodes (recommended use up to 10wt.% loading)
- Can be used to enhance existing graphite anode electrode active materials and is designed to provide improved cell capacity
- Typical initial anode capacity 400 – 450mAh/g
- Silicon based material designed for use in high loading anode electrode formulations (up to 80 wt.%)
- Significant increase in anode energy capacity and capacity density
- Mitigates expansion through the use of engineered porosity at the particle level in combination with optimised anode design