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Circular Economy of Energy Storage (C2E2)

Consortium for Circular Economy of Energy Storage ("C2E2")
Launched May, 2021

Stanford University is forming an academic-industrial consortium to co-innovate a circular economy for energy storage that meet the needs of the rapidly growing electric vehicle and grid storage markets. The need for a consortium is rooted in the interdisciplinarity required to tackle this grand challenge, crosscutting (1) technology for recycling, repurposing and remanufacturing, (2) decision-making tools informed by techno-economics and environmental footprint, (3) geographically- and market-specific business models, and (4) regulatory framework. The consortium will involve Stanford faculty members working across these areas and industry members engaged across the entire value chain of tomorrow’s circular economy. As a whole, the consortium will be well-positioned to engage with policymakers internationally and to advocate for industry-wide actions.

The consortium will consist of the core faculty, associated students and researchers, and StorageX industry members who commit to contribute one or more tokens per year to the consortium pool for 3 years.  The industry members will be referred to as the consortium industry members.

C2E2 Consortium industry member includes Shell, BASF, Redwood Materials

Funds from the pool will be used to support one or more of the following:  consortium seed projects, consortium research projects and associated researchers and students, consortium management, and consortium student internships.


3 Funded Projects in 2021

1. A Decision-Support Model for Retired Li-Ion Automotive Batteries

PI: Sally Benson, Simona Onori, Energy Resources Engineering. Will Chueh, Materials Science and Engineering
Benson Lab, Stanford Energy Control Lab, The Chueh Group

Today, electric vehicles (EVs) are the leading option for making transportation more sustainable, but with the ever-increasing growth of EVs, there is emerging concern about what to do with the retired batteries. The first wave of these retired batteries is expected by early EV adopters by 2025, with over 45,000 battery packs (containing tens of millions of Li-Ion cells) coming out of service. When batteries are retired from automotive service they still have from 50% to 70% of their initial capacity, which opens the possibility to repurpose them for other less demanding applications until they are eventually recycled. Possible applications include behind the meter energy storage for peak shaving, demand response, and power quality. Alternatively, grid-connected batteries also can provide frequency regulation, renewables smoothing, ramping support, and peak shaving, to name a few. Each of these 2nd life applications will place different demands on the battery, affecting its remaining useful life. There are four significant challenges to overcome to make repurposing or reusing retired batteries a viable option. Methods are needed to 1) quickly, affordably, and reliably assess the state-of-health of the battery pack/cells, 2) evaluate the remaining useful life of the pack/cells for different 2nd life applications, 3) determine the economic value of the pack/cells for sellers and buyers of repurposed batteries and 4) make repurposing batteries inexpensive enough to compete with the ever-declining costs of new Li-Ion batteries.  The goal of this project is to develop an integrated physics-based and technoeconomic model to assess whether a battery system coming out of automotive service should be recycled directly or has sufficient economic value to be repurposed for a particular 2nd life application, and if so, what is the value?

2. Fair Market Valuation of EV Batteries in the Circular Economy

PI: Stefan Reichelstein, Co-PI: Stephen Comello, Graduate School of Business.

With the share of EVs for transportation growing rapidly in many countries, it becomes imperative to examine economically viable use cases for batteries that are no longer suitable for primary mobile applications. This work seeks to conduct a micro-economic analysis of used batteries emerging from transportation-related applications that could be deployed in a second life, before moving to a recycling or disposal stage. The research will develop an economic valuation framework that determines the fair market value of batteries entering their 2nd-life based on their assessed state of health at the end of their first life. This fair market valuation will also consider the expected salvage value that end-of-life EV batteries are likely to yield once the nascent recycling industry for batteries reaches full scale.

3. Designing and Evaluating Battery Recycling Unit Processes

PI: Will Tarpeh, Chemical Engineering. Sally Benson, Ines Azevado, Energy Resources Engineering
Tarpeh Group, Benson Lab, Ines Research Group

The overall goal of the proposed research is to integrate the design of recycling processes with battery operation and supply chain logistics. Informing process design with practical battery performance requirements and more efficient logistics will accelerate the transition to a circular battery economy. Within this battery economy, we investigate element-specific recovery focused first on lithium, cobalt, and nickel. We pursue three complementary objectives in this proposal: (1) determine the effect of feedstock composition (e.g., homogeneous vs. mixed stream) on separation process performance; (2) evaluate the effect of centralization on the separation performance of novel battery recycling unit processes; and (3) establish relationships between separation process performance and battery performance. We focus on three classes of separation techniques: metallurgical, membrane, and adsorption processes. These efforts advance two C2E2 Research Pillars: new processing technology for recycling and environmental impact assessment tools.