A dual-functional gel-polymer electrolyte for lithium ion batteries with superior rate and safety performances. Issue 35 (29th August 2017)

• Record Type: Journal Article
• Authors: Li, Xilin; Qian, Kun; He, Yan-Bing; Liu, Cheng; An, Decheng; Li, Yiyang; Zhou, Dong; Lin, Zhiqun; Li, Baohua; Yang, Quan-Hong; Kang, Feiyu
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 35(2017)
• Page Start: 18888
• Page End: 18895
• Publication Date: 2017-08-29
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c7ta04415a
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : An attractive approach to fabricate high energy density and safe Li-ion batteries was proposed by utilizing a pentaerythritol tetraacrylate-based gel-polymer electrolyte. Abstract : The ability to judiciously utilize gel-polymer electrolytes (GPEs) that replace liquid electrolytes is widely recognized as an attractive route to solving the safety concerns of Li-ion batteries (LIBs). In this context, novel LiNi0.8 Co0.15 Al0.05 O2 (NCA)/graphite GPE and NCA/graphite–Si/C GPE batteries with high energy density and excellent electrochemical and safety performances are developed via in situ polymerization of pentaerythritol tetraacrylate (PETEA) in a liquid electrolyte. Notably, the capacity retention of NCA/graphite and NCA/graphite-Si/C GPE batteries after 200 cycles at the discharge rate of 5C is 92.5% and 81.2%, respectively, which are much larger than those implementing liquid electrolytes ( i.e., only 55.9% and 51.4%, respectively). Interestingly, the GPE batteries also displayed considerably lower gas production, especially the graphite-Si/C anode battery, and did not undergo a violent combustion during the nail penetration test compared to the liquid electrolyte batteries. The markedly enhanced performances noted above can be attributed to the three-dimensional framework of the GPE which promoted the formation of a very tight protective film on the surface of the electrodes during cycling, thereby inhibiting the cyclable Li consumption and side reactions with the electrolyte. Furthermore, such a protective film effectively retained the structural integrity of the electrodes during the cycling process and reduced the heat reactions between the electrodes and electrolyte.