Power, Army STTR, Phase I
Fast Charge Silicon Anode Lithium-Ion Cells for Small UAS Systems
Objective
Businesses must develop fast-charging, silicon anode lithium-ion cells for small Unmanned Aerial Systems.
Description
Fast-charging (less than 6 minutes) commercial graphite anode Li-ion cells to specific energies greater than 110 Wh/kg is a significant challenge. The inability to fast charge to higher specific energy means that more batteries must be in the logistics chain to supply operations. It also means that onboard/critical-edge charging is not an option for many fast-paced operations.
A promising technology in development for high energy Li-ion cells (300-400 Wh/kg) is based on silicon (Si) anodes that have demonstrated fast charge capability in prototype cells. The challenges with Si anode cells are cycle life, calendar life and safety. Many Si anode cell developers focus on achieving the highest energy batteries and not on the ability to fast charge with long cycle or calendar life.
Cell capacity, safety and cycle life typically suffer when Li-ion cells quickly charge. The limitations mainly relate to the graphite anodes inability to absorb lithium ions without plating lithium metal. Si anodes alloy with lithium and demonstrate capacities 10 times that of graphite at a potential and electrode thickness that make lithium plating much less likely under fast charge.
Si anode cycle life is lower than commercial graphite systems due to several factors, including the mechanical grinding of the Si alloy under repeated cycling. This leads to loss of active material contact as well as the continuous new surface generation and subsequent passivation that occur as the Si swells and contracts upon charge and discharge. Calendar life is poor in these systems, which limits the use in EV applications. However, for several specialty applications, the specific energy provides much needed capability.
Energy sharing between energy sources (vehicles, generators, solar chargers) and Soldiers already occurs when BB2590 batteries are charged in the field. The charging process is slow and it is often easier to swap to available batteries.
Fast charge batteries are part of the Combat Capabilities Development Command Army Research Laboratory’s Versatile Tactical Power and Propulsion Essential Research Program. They work in tandem with wireless recharge and silent power generation, which will eliminate battery swaps, reduce the cognitive and physical load on Soldiers and reduce the logistical tail in batteries.
One example is the use of fast charge batteries in small unmanned air systems charged from mobile ground stations that enable autonomous recharge. This frees the Soldier from carrying and changing batteries while reducing their exposure on the battlefield.
This topic seeks to develop Si based fast charge cells with demonstrated specific energy greater than 200 Wh/kg in 6 minutes of charge. This will enable new concepts in energy sharing, increased pace of operations and compact energy sources for high power devices. The topic looks to have Si anode materials brought further into development to demonstrate the improvements in full Li-ion cells for use in VICTOR ERP programs.
Phase I
In the Phase I effort, businesses must demonstrate single/few layer Si anode full cells that, when fast charged at 10C (6-minute) rates, cycle for >1000 continuous cycles at 3C discharge to >80% capacity. These cells should support the development of multi-Ah cells with a specific energy >200 Wh/kg. Deliverables should be 10 full cells of >100 mAh capacity capable of 10C charge / 3C discharge and >1000 cycles to >80% capacity.
Phase II
Phase II would involve producing and characterizing cells in sufficient quantities to fully characterize them for rate, temperature performance and continuous cycling stability. Deliverables include 20 full cells at a rated capacity of >2Ah capable of 10C/3C charge-discharge cycling at an energy density of >200 Wh/kg at the 10C charge rate.
Phase III
Technology applications could include storage for high energy storage modules, jammer applications, 6T battery applications and fast charge batteries in UAS systems. Commercial applications may include batteries for hybrid electric vehicles and eVTOL. If the Phase III program is successful, likely funding sources include Program Executive Office Soldier, Project Manager UAS and Command, Control, Computers, Communications, Cyber Defense, Intelligence, Surveillance and Reconnaisance.
Submission Information
All eligible businesses must submit proposals by noon ET.
To view full solicitation details, click here.
For more information, and to submit your full proposal package, visit the DSIP Portal.
STTR Help Desk: usarmy.rtp.devcom-arl.mbx.sttr-pmo@army.mil
References:
- Inorganics 2023, 11(5), 182; https://doi.org/10.3390/inorganics11050182
- Nature Nanotechnology, volume 3, pg 31–35 (2008)
- https://amprius.com/technology/
- https://arl.devcom.army.mil/what-we-do/victor/
- Fast charge, Lithium-ion, Silicon anode, High power
Objective
Businesses must develop fast-charging, silicon anode lithium-ion cells for small Unmanned Aerial Systems.
Description
Fast-charging (less than 6 minutes) commercial graphite anode Li-ion cells to specific energies greater than 110 Wh/kg is a significant challenge. The inability to fast charge to higher specific energy means that more batteries must be in the logistics chain to supply operations. It also means that onboard/critical-edge charging is not an option for many fast-paced operations.
A promising technology in development for high energy Li-ion cells (300-400 Wh/kg) is based on silicon (Si) anodes that have demonstrated fast charge capability in prototype cells. The challenges with Si anode cells are cycle life, calendar life and safety. Many Si anode cell developers focus on achieving the highest energy batteries and not on the ability to fast charge with long cycle or calendar life.
Cell capacity, safety and cycle life typically suffer when Li-ion cells quickly charge. The limitations mainly relate to the graphite anodes inability to absorb lithium ions without plating lithium metal. Si anodes alloy with lithium and demonstrate capacities 10 times that of graphite at a potential and electrode thickness that make lithium plating much less likely under fast charge.
Si anode cycle life is lower than commercial graphite systems due to several factors, including the mechanical grinding of the Si alloy under repeated cycling. This leads to loss of active material contact as well as the continuous new surface generation and subsequent passivation that occur as the Si swells and contracts upon charge and discharge. Calendar life is poor in these systems, which limits the use in EV applications. However, for several specialty applications, the specific energy provides much needed capability.
Energy sharing between energy sources (vehicles, generators, solar chargers) and Soldiers already occurs when BB2590 batteries are charged in the field. The charging process is slow and it is often easier to swap to available batteries.
Fast charge batteries are part of the Combat Capabilities Development Command Army Research Laboratory’s Versatile Tactical Power and Propulsion Essential Research Program. They work in tandem with wireless recharge and silent power generation, which will eliminate battery swaps, reduce the cognitive and physical load on Soldiers and reduce the logistical tail in batteries.
One example is the use of fast charge batteries in small unmanned air systems charged from mobile ground stations that enable autonomous recharge. This frees the Soldier from carrying and changing batteries while reducing their exposure on the battlefield.
This topic seeks to develop Si based fast charge cells with demonstrated specific energy greater than 200 Wh/kg in 6 minutes of charge. This will enable new concepts in energy sharing, increased pace of operations and compact energy sources for high power devices. The topic looks to have Si anode materials brought further into development to demonstrate the improvements in full Li-ion cells for use in VICTOR ERP programs.
Phase I
In the Phase I effort, businesses must demonstrate single/few layer Si anode full cells that, when fast charged at 10C (6-minute) rates, cycle for >1000 continuous cycles at 3C discharge to >80% capacity. These cells should support the development of multi-Ah cells with a specific energy >200 Wh/kg. Deliverables should be 10 full cells of >100 mAh capacity capable of 10C charge / 3C discharge and >1000 cycles to >80% capacity.
Phase II
Phase II would involve producing and characterizing cells in sufficient quantities to fully characterize them for rate, temperature performance and continuous cycling stability. Deliverables include 20 full cells at a rated capacity of >2Ah capable of 10C/3C charge-discharge cycling at an energy density of >200 Wh/kg at the 10C charge rate.
Phase III
Technology applications could include storage for high energy storage modules, jammer applications, 6T battery applications and fast charge batteries in UAS systems. Commercial applications may include batteries for hybrid electric vehicles and eVTOL. If the Phase III program is successful, likely funding sources include Program Executive Office Soldier, Project Manager UAS and Command, Control, Computers, Communications, Cyber Defense, Intelligence, Surveillance and Reconnaisance.
Submission Information
All eligible businesses must submit proposals by noon ET.
To view full solicitation details, click here.
For more information, and to submit your full proposal package, visit the DSIP Portal.
STTR Help Desk: usarmy.rtp.devcom-arl.mbx.sttr-pmo@army.mil
References:
- Inorganics 2023, 11(5), 182; https://doi.org/10.3390/inorganics11050182
- Nature Nanotechnology, volume 3, pg 31–35 (2008)
- https://amprius.com/technology/
- https://arl.devcom.army.mil/what-we-do/victor/
- Fast charge, Lithium-ion, Silicon anode, High power