Project Overview

Focus of this project was to establish potassium-ion battery (KIB) technology as a sustainable, cost-effective alternative to lithium-ion batteries (LIBs). Building on the invention of the Potassium Prussian White cathode at the University of Texas at Austin, Group1 successfully demonstrated a 200mAh KIB pouch cell in 2023. This achievement showcased strong cycling stability and high coulombic efficiency in a larger cell format, marking a significant advancement since KIB’s inception. Despite these milestones, the KIB pouch cell’s rate capability remained a critical limitation, restricting its potential for energy storage applications. This Phase I project addressed these challenges by deploying advanced analytical and electrochemical techniques while integrating innovations in battery chemistry, materials science, electrode design, and KIB cell architecture. The primary objective was to develop a >200mAh KIB cell capable of reliable operation at 1C–C/3 charge/discharge rates with at least 70% capacity retention.

Intellectual Merit

This Small Business Technology Transfer Phase 1 project addresses the key Big Question in “Beyond Li-Ion” energy storage systems: Why do non-Li architectures that should in principle function as well as Li architectures fall short at faster charging rates and how can this be resolved? While individual (anode, cathode, electrolyte) non-Li components are highly promising in terms of charge transfer and storage behavior, why does the holistic system fall short? In a broader sense, resolving this quandary should potentially enable other earth abundant non-Li architectures to become viable, enabling a domestically sourced energy systems to flourish. The commercially focused effort operates at the core of structure- functional properties relations non-Li systems, where there is markedly much less understanding versus existing LIBs. The project unraveled key structure-properties relations in the nominally more reactive K-based architectures. This effort allowed for a broad spectrum of learning, starting at basic mechanistic insight at meso scale and advancing to commercially relevant KIB cell testing.

Key Achievements

The project successfully delivered a 3.62V KIB 18650 battery, achieving the final milestone outlined in our proposal with the targeted performance. The cell maintained over 70% capacity retention at a 1C charge rate and demonstrated enhanced cycling stability compared to the 200mAh pouch cell, underscoring its durability. Additionally, the KIB technology has advanced from lab-scale development to roll-to-roll electrode coating and semi-automatic cell assembly.

Broader Impacts

LiBs are crucial for both electric vehicles and grid energy storage, but shortages in critical materials and vulnerable supply chains could lead to a significant shortfall in battery production. This, in turn, would compromise the progress towards reducing greenhouse gas emissions. To address this crisis, developing alternative technologies like KIBs are crucial. Potassium is abundantly available, domestically sourced, and offers a sustainable solution with a reduced risk of supply chain disruptions. The adoption of KIBs not only reduces the demand for lithium but also mitigates supply chain risks. It offers a more sustainable solution across various industries, creating opportunities for economic growth, job creation, and technological advancement. Group1's KIB can be a viable alternative to LIB that can contribute significantly to a more sustainable future. Commercializing KIB technology will enable Li-free sustainable alternatives LIBs for EV and grid storage applications.

Last Modified: 02/10/2025
Modified by: Leigang Xue