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Our technology enables Li-ion batteries to store previously unattainable levels of energy – the highest capacity in the world.
Envia is a high energy density leader in the lithium-ion battery space, having developed intellectual property and cell prototypes using Envia cathode, anode and electrolyte. Envia is engaged with automotive OEMs around the world – developing custom cathode material, electrolyte and cell designs for these OEMs automotive applications. As a proof of technical leadership, Envia has also demonstrated the world’s first 400Wh/kg in large format pouch cells.Envia received an R&D 100 Award for making an electric vehicle battery with the highest energy density. Read more »
The key to achieving the world record energy density is combining Envia’s proprietary high capacity HCMR™ cathode with its proprietary high capacity Si-C anode.
Current Cathodes
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Ordered Rocksalt
Layered
LiMo2
(M=Co, Ni, Mn) - Crystal Structure
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Characteristics
- Capacity limited to ~0.5 Li per M atom (~140 mAh/g)
- Co4+ and Ni4+ unstable/highly oxidizing
- Structure destabilized at low Li content
- Layered LiMnO2 transforms to spinel
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Spinel
LiM2O4
(M=Mn) 
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- Capacity limited to <0.5 Li/Mn at 4V
- Robust M2O4 spinel framework; 3D channels
- High rate capability
- Jahn-Teller distortion at 3V
- Solubility problems at high potentials
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Olivine
LiMPO4
(M=Fe, Mn) 
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- Capacity limited to 1 Li/Fe; P inactive
- Excellent structural stability; 1D channels
- Poor electronic and Li-ion conductivity
- Poor packing density
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Layered-Layered
xLiMn2O3.(1-x)LiMO2
(M=Co, Ni, Mn) 
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- Li2MnO3 electrochemically inactive; where as LiMO2 is active with respect to Lithium insertion/extraction
- Strategy: Embed inactive Li2MnO3 component within layered LiMO2 structure to stabilize electrode and reduce oxygen activity at surface of charged particles
Source: Dr. Michael Thackeray, Argonne National Laboratory
Envia’s Cathode
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Envia has a unique cathode chemistry based on a unique crystal structure. It’s High Capacity Manganese Rich (HCMR™) cathode has excellent stability at high voltages and can access high capacities with long cycle life. Our proprietary nanocoating processes further enhance cycle life (>1000 at 100% DoD). Envia has built on Argonne’s layered-layered chemistry to fine tune the composition of Ni, Co, Mn and Li2MnO3. We have innovated on particle morphology (particle size, shape, distribution, tap density & porosity). Finally, we have developed novel nanocoatings to enhance cycle life & safety.
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Anodes
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Under the auspices of the ARPA-E grant, Envia has been able to demonstrate very high capacity (1530 mAh/g) and promising cycle life performance using silicon-carbon nanocomposite anodes. We successfully achieved the ARPA-E program goal to produce a battery with an energy density of 400 Wh/kg. We are currently scaling up the material using a low cost production process. This anode will be ready for commercialization in 2012 and will complement Envia’s high capacity cathode very well.
Electrolytes
Envia has developed an electrolyte that is stable up to a voltage of 5.2V (vs Li/Li+). In cyclic voltammetry studies of standard electrolytes, as the voltage window was opened from upper cut-off of 4.3V vs Li/Li+ the electrolytes showed an increase in oxidation currents. When the voltage window was further increased to voltages above 4.5V the oxidation currents increased significantly showing that the electrolytes were almost completely oxidized at these voltages. However, Envia’s High Voltage Electrolyte showed stability up to 5.2V without any rapid increase in the oxidation currents.
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Envia’s highest capacity anodes
Envia’s Technology Progression
Envia has a product roadmap to achieve the highest levels of energy density.
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