2012 R&D 100 Award Winner

The Invention 

A unique method to control the composition gradient of materials in lithium-ion cathodes. The material particles created using this method are nickel-rich on the inside for a high capacity battery, and manganese-rich on the exterior surface for increased safety and stability. 

The process includes combining a first transition metal compound with a second transition metal compound to form a transition metal source solution, and combining that solution with a precipitating agent to form a precursor solution. The radius of precipitating particles consists of a transition metal oxide core and at least two layers of transition metal oxide. The particles have a transition metal concentration gradient in which the ratio of the first transition metal to the second transition metal is inversely proportional to the radius of the particle over at least a portion of the radius. The transition metal used in the first and second transition metal compounds include manganese, cobalt, nickel, chromium, vanadium, aluminum, zinc, sodium, titanium or iron. The first and second transition metal compounds can also include, but are not limited to, metal sulfates, nitrates, halides, acetates or citrates. 

Benefits 

• Creates a gradient of different materials for increased safety and stability; 
• Gradient runs throughout the entire radius of the particle; 
• Particles are ideally small, 10-20 microns in size; and 
• Leads to high-capacity batteries. 

Applications and Industries 

The particles can be used to create composite cathodes in batteries for 

• Electric and plug-in hybrid electric vehicles; 
• Portable electronic devices; 
• Medical devices; and 
• Space, aeronautical, and defense-related devices. 

Developmental Stage 

Reduced to practice 

Technology Overview 

Argonne’s family of manganese and lithium rich materials includes a range of cathode structures, including layered-type structures, spinel-type structures, rocksalt-type structures, and combinations thereof. For example, ​“layered-layered-spinel” materials with high-rate and stable voltage that are composed of lithium manganese nickel oxides have been discovered and can be used to replace high-energy multi- component ​“layered-layered” type or single-phase high-rate spinel-type structures for lithium cells and batteries. 
See Surface structures, treatments and coatings for high-voltage lithium metal oxide electrodes for complementary surface treatment and coating technologies. 

Benefits 

• These new material compositions provide substantially higher capacities than state-of-the-art layered lithium/cobalt/nickel/oxide materials, such as nickel-manganese-cobalt (NMC).
• Due to the spinel component, these cathodes are endowed with high power where they can be charged and discharged rapidly. 
• The multi-component nature of these materials can be optimized in the phase space in the figure according to the manufacturer’s needs. 
• Manganese is less expensive to use and more chemically benign than cobalt or nickel. Either low-cost elements and/or other elements may be doped into the structure to provide better performance, at a lower cost, as needed.

Applications and Industries 

Electrodes used in batteries for: 

• Electric and plug-in hybrid electric vehicles,
• Stationary energy storage systems,
• Portable electronic devices, 
• Medical devices, and 
• Space, aeronautical, and defense-related devices. 

Developmental Stage 

Ready for commercialization. 

Lithium metal is an attractive anode material for rechargeable batteries in terms of its extremely high theoretical capacity (3860 mAh/g) and the lowest negative potential (-3.040 V, versus the standard hydrogen electrode). However, lithium dendrite formations during electrochemical cycling cause severe capacity fade and cell failure due to electrical shorting or electrolyte consumption. This tricky problem has prevented the incorporation of lithium anodes in commercial rechargeable cells due to potential safety issues and limited cycling life. 

This patent technology uses a protective coating that can greatly suppress the dendrite formation of lithium anodes and improve the lithium cycling stability. The protective coating is synthesized using a chemical vapor process that yields uniform and conformal films. The films are composed of a proprietary material that is mechanically robust to suppress lithium dendrites and has a high lithium ion conductivity and low electrical conductivity. The applications of rechargeable batteries with lithium anodes include portable devices and electric vehicles. 

Divisional patent application 16/741,434

Benefits

• Additives enable excellent specific power and energy and extended calendar life 
• Work across broad temperature range with minimal or no capacity loss