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Vol. 18 (2026)

Bioinspired Injection Therapy for Spent LiFePO4 Batteries: A Non-Invasive Strategy for Capacity Regeneration and Longevity Enhancement

https://doi.org/10.1007/s40820-026-02091-1
Peng Wang
Hebei Key Laboratory of Flexible Functional Materials, School of Materials Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, People’s Republic of China
Jian Wang
Hebei Key Laboratory of Flexible Functional Materials, School of Materials Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, People’s Republic of China
Longwei Bai
Hebei Key Laboratory of Flexible Functional Materials, School of Materials Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, People’s Republic of China
Na Li
Hebei Key Laboratory of Flexible Functional Materials, School of Materials Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, People’s Republic of China
Chuancong Zhou
State Key Laboratory of Tropic Ocean Engineering Materials and Materials Evaluation, School of Materials Science and Engineering, Hainan University, Haikou 570228, People’s Republic of China
Mingyang Chen
State Key Laboratory of Tropic Ocean Engineering Materials and Materials Evaluation, School of Materials Science and Engineering, Hainan University, Haikou 570228, People’s Republic of China
Jialiang Zhang
State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, No. 30 Xueyuan Road, Haidian District, Beijing 100083, People’s Republic of China
Zhenyue Xing
State Key Laboratory of Tropic Ocean Engineering Materials and Materials Evaluation, School of Materials Science and Engineering, Hainan University, Haikou 570228, People’s Republic of China
Zaowen Zhao
State Key Laboratory of Tropic Ocean Engineering Materials and Materials Evaluation, School of Materials Science and Engineering, Hainan University, Haikou 570228, People’s Republic of China
Wei Zhang
Christopher Ingold Laboratory, Department of Chemistry, University College London, London WC1H 0AJ, UK
Xiaodong Shi
State Key Laboratory of Tropic Ocean Engineering Materials and Materials Evaluation, School of Materials Science and Engineering, Hainan University, Haikou 570228, People’s Republic of China

Corresponding Author: Xiaodong Shi

shixiaodong@hainanu.edu.cn

Nano-Micro Letters, Vol. 18 (2026), Article Number: 245

Abstract

The widespread deployment of lithium iron phosphate (LiFePO4, LFP) batteries has intensified the imperative to address the disposal challenges associated with retired LFP batteries, given their rapidly growing volumes. However, existing regeneration techniques remain constrained by their inherent complexity, high energy demands, and limited scalability, posing significant barriers to achieving efficient and economically viable solutions. Herein, inspired by medical injection therapy, a novel, non-invasive strategy for direct capacity rejuvenation is proposed by injecting recovery reagents into spent LFP batteries, circumventing the need for disassembly. This innovative approach leverages the I3−/I− redox couple to activate residual/dead lithium on the graphite anode and selectively re-engineer the solid electrolyte interphase (SEI), preserving its functional components while optimizing interfacial dynamics. The restored lithium from the anode serves as an intrinsic source to replenish lithium deficits and rectify Li–Fe antisite defects within the degraded LFP cathode. The resulting regenerated pouch cells demonstrate remarkable recovery of electrochemical capacity, accompanied by superior kinetics performance and significantly extended cycle life. This pioneering strategy not only delivers an energy-efficient and cost-effective pathway for LFP battery regeneration but also holds transformative potential to redefine sustainable practices in lithium-ion battery reuse, thereby advancing their practical applications and prolonging their service life.


Highlights:
1 An effective and facile injection strategy based on iodine redox chemistry is proposed to restore lost lithium component in spent LiFePO4 battery.
2 In-situ spectroscopic characterization is conducted to unveil the underlying redox mechanism of iodine-mediated lithium reactivation, elucidating its impact on both the cathode and anode.
3 Regenerated LiFePO4 cells exhibit ~ 7% capacity recovery, fast charge transfer behavior, and extended cycle life beyond 300 cycles at 1C, outperforming conventional direct recycling methods while maintaining superior cyclic stability.

Keywords

Spent LFP batteries Direct regeneration I3 −/I− redox couple Dead lithium Lithium replenishment
Wang, Peng, Jian Wang, Longwei Bai, Na Li, Chuancong Zhou, Mingyang Chen, Jialiang Zhang, Zhenyue Xing, Zaowen Zhao, Wei Zhang, and Xiaodong Shi. 2026. “Bioinspired Injection Therapy for Spent LiFePO4 Batteries: A Non-Invasive Strategy for Capacity Regeneration and Longevity Enhancement”. Nano-Micro Letters 18 (February):245. https://doi.org/10.1007/s40820-026-02091-1.
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