Aqueous Li-ion batteries (ALIBs) are an important class of battery chemistries owing to the intrinsic non-flammability of aqueous electrolytes. However, water is detrimental to most cathode materials and could result in rapid cell failure. Identifying the degradation mechanisms and evaluating the pros and cons of different cathode materials are crucial to guide the materials selection and maximize their electrochemical performance in ALIBs. In this study, we investigate the stability of LiFePO4(LFP), LiMn2O4(LMO) and LiNi0.8Mn0.1Co0.1O2(NMC) cathodes, without protective coating, in three different aqueous electrolytes, i.e., salt-in-water, water-in-salt, and molecular crowding electrolytes. The latter two are the widely reported “water-deficient electrolytes.” LFP cycled in the molecular crowding electrolyte exhibits the best cycle life in both symmetric and full cells owing to the stable crystal structure. Mn dissolution and surface reduction accelerate the capacity decay of LMO in water-rich electrolyte. On the other hand, the bulk structural collapse leads to the degradation of NMC cathodes. LMO demonstrates better full-cell performance than NMC in water-deficient aqueous electrolytes. LFP is shown to be more promising than LMO and NMC for long-cycle-life ALIB full cells, especially in the molecular crowding electrolyte. However, none of the aqueous electrolytes studied here provide enough battery performance that can compete with conventional non-aqueous electrolytes. This work reveals the degradation mechanisms of olivine, spinel, and layered cathodes in different aqueous electrolytes and yields insights into improving electrode materials and electrolytes for ALIBs. 
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                            Operational strategies of pulsed electrolysis to enhance multi-carbon product formation in electrocatalytic CO 2 reduction
                        
                    
    
            Different operational strategies of pulsed electrolysis lead to different origins for the enhancement of multi-carbon product formation in electrocatalytic CO2reduction. 
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                            - Award ID(s):
- 2033343
- PAR ID:
- 10565177
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- EES Catalysis
- Volume:
- 2
- Issue:
- 4
- ISSN:
- 2753-801X
- Page Range / eLocation ID:
- 997 to 1005
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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