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The higher specific capacity and richness in natural resources makes SiOx-based become a research focus by international scholar in recent years. A lot volume changes of material in the process of cycling which affects the batteries’ cycling performance, thereby limiting its development and usage. While choosing suitable binder is critical to effectively enhance the performance of the silicon oxide (SiOx) that has high specific capacity and easy pulverization. Researched the lithium insertion/extraction properties of SiOx composite electrode which prepared with polyvinylidene fluoride (PVDF), LA132 (which major copolymerization chain is polyacrylonitrile-polyacrylic acid (PAN-PAA)), polyacrylic acid (PAA). Electrochemical cycling tests with a current density of 160mA/g shows that SiOx electrode with conventional binder PVDF results in rapid capacity loss, while aqueous binder LA132 and PAA could dramatically improve cycle performance of SiOx. SiOx with PAA electrode exhibits reversible capacity still up to 1090mAh/g after 50 cycles. The analysis and characterization methods of SEM, EIS, XRD and differential capacity plots, it is prove that amorphous or little crystalline binder have physical or chemical reaction with –OH of SiOx and formed class network constitute. The expansion pulverization of SiOx power limited in original domain and maintained electronic and ionic conductivity effectively, improved cycle performance of materials. Acknowledgements The project was supported by the Shanghai Science and Technology Development Fund (15DZ2282000). References [1] J. Li, L. Christensen, M. N. Obrovac, K. C. Hewitt and J. R. Dahn. J. Electrochem. Soc., 155(2008): A234-A238. [2] N. S. Hochgatterer, M. R. Schweiger, S. Koller, P. R. Raimann, T. Wöhrle, C.Wurm and M. Winter. Electrochem. Solid-State Lett. 11(2008): A76-A80. [3] X. J. Feng, J. Yang, X. L. Yu, Wang J L, Y. N. Nuli. J. Solid State Electrochem, 17(2013):2461-2469. [4] I. Kovalenko, B. Zdyrko, A. Magasinski, B. Hertzberg, Z. Milicev, R. Burtovyy, I. Luzinov, G. Yushin. Scicence, 334(2011):76-79. Figure 1

As the world into the era of 3G/4G, 3G/4G phones and netbooks gradually popular, mobile Internet, games, video more extensive application of all these applications need to be on the phone for a long time operation, the need of mobile phone battery can support a long time, it puts forward higher requirements on lithium ion batteries, thus to improve the specific energy of lithium ion battery has become one of the problems to be solved1-2. At present mainly in order to improve the specific energy of lithium ion battery by boosting voltage of LiCoO2 material, while it will also bring adverse effect to LiCoO2 materials. So it is necessary to study the evolution of the LiCoO2under high voltage cycling. In this paper, we used the three electrodes to monitor the potential changes of LiCoO2 and graphite from the battery initial state charged to 4.5 V (as shown in figure 1), and before and after cycling. Study the morphology, structure and surface changes of LiCoO2before and after cycling under 4.5V high voltage by using differential capacitance, scanning electron microscopy, X-Ray Diffraction (as shown in figure 2), Raman, IR and differential scanning calorimetry analysis characterization methods. Acknowledgements The project was supported by the Shanghai Science and Technology Development Fund (15DZ2282000) and (14JC1491800) References [1]. A. Aboulaich*, K. Ouzaouit, H. Faqir, A. Kaddami, I. Benzakour, I. Akalay. Materials Research Bulletin 73 (2016) 362-368. [2]. Y. Ito, Y. Sakurai, S. Yubuchi, A. Sakuda, A. Hayashi∗,and M. Tatsumisago, J. Electrochem. Society, 162 (8) (2015) A1610-A1616. Figure 1

With the increasing applications of lithium ion batteries in energy storage, electric vehicles and hybrid electric vehicles, it’s required to improve the energy density, safety, rate capability and cycling stability of the batteries. Spinel Li4Ti5O12 is a promising anode material for lithium-ion batteries which possesses good Li+ insertion and de-insertion reversibility with negligible structure change, high safety and rate capability, excellent cycle stability1-2. While the theoretical capacity of it, 175 mAh g-1, is slightly low. Meanwhile, it’s observed gassing during storage or cycling3, limitting its application.It was found that the surface coating could be an effective method to solve the swelling problem and be beneficial to the electrochemical performance4. In this paper, we investigated the effect of titanate coupling reagent TCA-K38S as electrolyte additive on the performance of Li4Ti5O12. TCA-K38S, isopropyl tri-(dioctylpyrophosphate) titanate, is a liquid monoalkoxy pyrophosphate titanate, usually used as coupling agent not only finorganic fillers with resins, but also fnon-polar materials with polar materials, the structural formula is shown in Fig.1. The electrolyte used in this work are 1.2 mol LiPF6 in EC/ EMC solvents ((3:7 by volume), the TCA-K38S was added at 1wt.% and 3 wt.% to the electrolyte solution. Fig.2 shows the cycling performance of Li4Ti5O12 batteries with different amounts of the TCA-K38S additive at various rates. It can be seen that the specific capacity of batteries with 1wt.% additive is 180 mAh g-1 at the first discharge and stable in 170mAh g-1 at 0.2 C, comparied to 162mAh g-1 and 158mAh g-1 at 0.2 C when it’s without additives. Acknowledgements The project was supported by the National High Technology Research and Development Program of China (863) (2013AA050902) and Shanghai Science and Technology Development Fund (15DZ2282000, 14JC1491800) . References [1]. Z. Huang, D. Wang, Y. Lin, X.Y. Wu, P. Yan, C.M. Zhang, D.N. He, J. Power Sources, 266 (2014) 60-65. [2]. E. Pohjalainen , J. Kallioinen , T. Kallio, J. Power Sources, 279 (2015) 481-486. [3]. K. Wu, J. Yang, Y. Liu, Y. Zhang, C. Y. Wang, J.M. Xu, F. Ning, D.Y. Wang, J. Power Sources, 237 (2013) 285-290. [4]. Z.J. Ding, L. Zhao, L.M. Suo, Y. Jiao, S. Meng, Y.S. Hu, Z.X. Wang, L.Q. Chen, Phys. Chem. Chem. Phys., 2011, 13, 15127–15133. Figure 1