Li-ion batteries material

Originally, this referred specifically to layered structures that can undergo insertion of ions or molecules between the van der Waals gaps, but is now commonly used for any structure that undergoes topotactic insertion reactions. For Li-ion battery materials, it refers specifically to compounds that undergo reductive insertion of lithium ions, such as graphite (used as an anode) or LiCo02 (used as a cathode). 

Su L, Jing Y, Zhou Z (2011) Li ion battery materials with core-shell nanostructures. Nanoscale 3 3967-3983 and references therein... 

D and 3D Imaging of Li-Ion Battery Materials Using Synchrotron Radiation... 

Zaghib K, Mauger A, Groult H, Goodtaiough JB, Julien CM (2013) Advanced electrodes for high power Li-ion batteries. Materials 6 1028-1049... 

Samarasingh P, Tran-Nguyen DH, Behm M, Wijayasinghe A (2008) LiNii/3Mni Coi 02 synthesized by the Pechini method for the positive electrode in Li-ion batteries material characteristics and electrochemical behaviour. Electrochim Acta 53 7995-8000... 

Meiot BC, Rousse G, Chotard JN, Ati M, Rodriguez-Carvajal J, Kemei MC, Tarascon JM (2011) Magnetic structure and properties of the Li-ion battery materials FeS04p and LiFeS04p. Chem Mater 23 2922-2930... 

It is clear that there is enormous activity in the the search for better and cheaper anode materials for Li-ion batteries. In fact, it is not certain at this time whether carbon will remain the material of choice for this application. Nevertheless, large strides toward the optimization and understanding of carbons for Li-ion batteries have been made in the last 5 to 10 years. If continued progress is made, we can expect to see carbon materials in Li-ion batteries for a long timx to come. 

Chapter 11 reports the use of carbon materials in the fast growing consumer eleetronies applieation of lithium-ion batteries. The principles of operation of a lithium-ion battery and the mechanism of Li insertion are reviewed. The influence of the structure of carbon materials on anode performance is described. An extensive study of the behavior of various carbons as anodes in Li-ion batteries is reported. Carbons used in commereial Li-ion batteries are briefly reviewed. 

The Li-Ion system was developed to eliminate problems of lithium metal deposition. On charge, lithium metal electrodes deposit moss-like or dendrite-like metallic lithium on the surface of the metal anode. Once such metallic lithium is deposited, the battery is vulnerable to internal shorting, which may cause dangerous thermal run away. The use of carbonaceous material as the anode active material can completely prevent such dangerous phenomenon. Carbon materials can intercalate lithium into their structure (up to LiCe). The intercalation reaction is very reversible and the intercalated carbons have a potential about 50mV from the lithium metal potential. As a result, no lithium metal is found in the Li-Ion cell. The electrochemical reactions at the surface insert the lithium atoms formed at the electrode surface directly into the carbon anode matrix (Li insertion). There is no lithium metal, only lithium ions in the cell (this is the reason why Li-Ion batteries are named). Therefore, carbonaceous material is the key material for Li-Ion batteries. Carbonaceous anode materials are the key to their ever-increasing capacity. No other proposed anode material has proven to perform as well. The carbon materials have demonstrated lower initial irreversible capacities, higher cycle-ability and faster mobility of Li in the solid phase. 

The model cylindrical Li-ion battery (AA-size) was manufactured using SL-20 graphite as anode active material. The general appearance of the cells is shown by Figure 2 for more detailed description of the cells see the experimental part of the paper. 

Composite electrodes made of two carbon components were evaluated experimentally as anodes for Li-ion batteries. The electrochemical activity of these electrodes in the reaction of reversible lithium intercalation ffom/to a solution of LiPF6 in ethyl carbonate and diethyl carbonate was studied. Compositions of the electrode material promising for the usage in Li-ion batteries were found. 

Therefore, there is a wide spectrum of carbon materials suitable for the usage in Li-ion batteries the choice of a specific one determined by many factors. According to Ref. 7, the percentage of various carbon materials used in commercial Li-ion batteries was as follows graphites - 43 %, hard carbons - 52 %, soft carbons - 5 %. 

Thus, the electrochemical properties of the individual carbon materials are not so high as to enable their commercial usage in Li-ion batteries. In order to improve the performance, we started making composite materials from two individual carbon ingredients. Figure 1 shows a typical result of electrochemical tests of an electrode made of a blend of graphite and soft carbon treated at 1100°C (Cl 100) in comparison with the discharge curves of the individual constituents. 

SURFACE TREATED NATURAL GRAPHITE AS ANODE MATERIAL FOR HIGH-POWER LI-ION BATTERY APPLICATIONS... 

In conclusion, the surface modified natural graphite has good performance in PC based electrolyte and also meets the power requirements for hybrid electrical vehicle applications. Surface carbon coated natural graphite SLC1015 is a very promising material in high power Li-ion batteries with lower cost, reasonable safety, and low irreversible capacity. 

S. Bourderau, T. Brousse, D.M. Schleich. Amorphous silicon as a possible anode material for Li-ion batteries Journal of Power Sources 1999 81-82 233-36. 

Further on, the Co-Ni complexes were used for modification of Hohsen Carbon type (10-10) and Hohsen Graphite type (10-28) anode materials for Li-ion batteries applying similar procedure. These anode materials were tested in 2016 size lithium coin cells with a configuration Li/electrolyte (LP-30)/(modified anode material). The coin cells were assembled by standard technology in dry atmosphere of a glove box and then... 

---