Solid-State DC-DC Power Electronics for Grid-Scale Lithium EV Battery Pack Integration
This project will develop and optimize a DC-DC power conditioning system to enable use of second life electric vehicle batteries in grid storage applications.
EPC Power Corp.
Recipient
Poway, CA
Recipient Location
40th
Senate District
75th
Assembly District
$2,296,802
Amount Spent
Active
Project Status
Project Update
In 2023, the project is continuing to move along on schedule with two parallel, technological development activities: EPC is working on development of a low cost DC to DC converter, and Smartville is repurposing second life car batteries for use as grid scale battery storage devices. In the near future, the devices will be married to form a single energy storage system.
Testing of the coupled system is scheduled to begin in 2024. EPC will help physical integration and oversee the start of testing.
The Issue
Low-cost, reliable, and safe energy storage is critical for the State of California to achieve its renewable energy and decarbonization goals. Approximately 150 MWhs of new lithium-ion batteries are sold into California’s rapidly growing EV market each week, a volume that dwarfs the amount of storage deployed in stationary applications. As these batteries are decommissioned from the transport sector for a variety of reasons, they can be repurposed for stationary applications at lower costs than new batteries. However, achieving lower costs requires improvements to power electronics systems, storage system designs, and integrated systems engineering to successfully scale product offerings while meeting the strict reliability and safety requirements demanded by the grid-tied stationary energy storage sector.
Project Innovation
This project is to design and construct an innovative integrated power electronics / energy storage system to serve the grid-tied energy storage market. The system will be rated for 1 MW power and 1 MWh energy and use repurposed/2nd life electric vehicle (EV) packs.
Specific tasks include:
- Conduct power electronics topology assessment for a DC-DC converter to supply a regulated 500 VDC and 1000 VDC.
- Develop BMS noise immunity system (hardware and software).
- Develop power electronics DC-DC converter for either the 500 VDC supply or the 1,000 VDC supply to the Modular Assembly Battery (MoAB™) system inverter
- Integrate the DC-DC power electronics architecture with the BMS noise immunity system, the voltage leakage detection system, the retired EV packs, and the system inverter, and construct the 250 kW / 250 kWh MoAB unit.
- Conduct MoAB validation and testing at the system level.
- Install, commission, and demonstrate the MoAB unit functions and capabilities.
Project Goals
Project Benefits
In order to provide the market with an integrated energy storage system that can be grid-tied, the designed system will use 2nd life EV packs to incorporate recycling of used electronics.
Consumer Appeal
The consumer appeal benefit of this project is that the project will demonstrate a low-cost, easy-to-integrate second-life Modular Assembly Battery (MoAB™) with innovative DC-DC power electronics and the controls necessary to enable integration into utility-scale and commercial energy storage systems.
Affordability
Customers will benefit from lower cost energy systems, because the systems use second-life electric vehicle (EV) batteries.
Economic Development
This project has set out to prove that second-life electric vehicle (EV) batteries can be cost-effectively processed within California, instead of the current practice of sending these batteries overseas for processing, which could help support a lithium-ion battery circular economy and promote domestic manufacturing of lithium-ion batteries in California.
Environmental Sustainability
By using second-life electric vehicle (EV) batteries to create energy storage systems, this project plans to reduce the following in an effort to benefit both the environment and public health: nickel, cobalt, and lithium extraction due to the use of repurposed battery packs; and NOx and particulate emissions due to fewer gas turbine start-ups, runtime, and standby operations as a result of increased low-cost energy storage systems.
Equity
The recipient plans to develop the power electronics portion of the project into an economically viable solution for integration into the second-life Modular Assembly Battery (MoAB™) unit and demonstrate this technology for one year at an under-resourced community facility in San Joaquin, California.
Reliability
Using second-life electric vehicle (EV) batteries to create energy storage systems for utility-scale and commercial energy storage needs will reduce the overall cost of the systems, which in turn will increase the likelihood of a higher adoption rate of energy storage systems and with it an increase in energy reliability.
Energy Security
Using second-life electric vehicle (EV) batteries to create energy storage systems for utility-scale and commercial energy storage needs will reduce the overall cost of the systems, which in turn will increase the likelihood of a higher adoption rate of energy storage systems and with it an increase in energy security in the utility and commercial sectors.
Key Project Members
Devon Dilley
Alec Graham
Eric Hermin
Rachel Lindsay
Jake Ohlendorf
Subrecipients
Wellhead Electric Company, Inc
Smartville, Inc.
We Build Machines, LLC
Renewance Inc.
Match Partners
EPC Power Corp.
Smartville, Inc.
