Lithium-ion batteries chemistry

Tests were performed on three lithium-ion battery chemistries to determine the fraction of the Ah capacity that could he returned without current taper. The results of the testing are summarized in Table 3.5. The LTO chemistry has a clear advantage over the other chemistries especially compared to the nickel cobalt manganese oxide chemistry for fast charging. 

Cell Voltage The voltage of each individual cell in the battery pack is monitored on a continuous basis. Depending on the specific lithium-ion battery chemistry that is used, the upper voltage limit on charge, as specified by the manufacturer, is usually limited between 4.1 to 4.3 volts. On discharge, the cell voltage should not fall below 2.5 to 2.7 volts. 

T. Ohzuku, and Y. Makimura, Layered lithium insertion material of LiNii/3Coi/3Mni/302 for lithium-ion batteries, Chemistry Letter, 30 (2001), 642-643. 

YU M X and ZHOU x (2002), Recent development of polymer electrolytes for lithium ion batteries . Chemistry, 4 234-243... 

The work presented in this chapter involves the study of high capacity carbonaceous materials as anodes for lithium-ion battery applications. There are hundreds and thousands of carbonaceous materials commercially available. Lithium can be inserted reversibly within most of these carbons. In order to prepare high capacity carbons for hthium-ion batteries, one has to understand the physics and chemistry of this insertion. Good understanding will ultimately lead to carbonaceous materials with higher capacity and better performance. 

The chemistry of lithium-ion batteries is based on the lithium-ion shuttling between the graphite negative electrode and the transition metal(s) oxide positive electrode. The overall reaction can be schematized as ... 

Yoshio, M., Wang, H., Fukuda, Abe, T., and Ogumi, Z., Soft carbon-coated hard carbon beads as a lithium-ion battery anode material, Chemistry Letters (2003) Vol. 32, No. 12, 1130-1131. 

Vinayan, B.P., et al., Synthesis of graphene-multiwalledcarbon nanotubes hybrid nanostructure by strengthened electrostatic interaction and its lithium ion battery application. Journal of Materials Chemistry, 2012. 22(19) p. 9949-9956. 

ZnO displays similar redox and alloying chemistry to the tin oxides on Li insertion [353]. Therefore, it may be an interesting network modifier for tin oxides. Also, ZnSnOs was proposed as a new anode material for lithium-ion batteries [354]. It was prepared as the amorphous product by pyrolysis of ZnSn(OH)6. The reversible capacity of the ZnSn03 electrode was found to be more than 0.8 Ah/g. Zhao and Cao [356] studied antimony-zinc alloy as a potential material for such batteries. Also, zinc-graphite composite was investigated [357] as a candidate for an electrode in lithium-ion batteries. Zinc parhcles were deposited mainly onto graphite surfaces. Also, zinc-polyaniline batteries were developed [358]. The authors examined the parameters that affect the life cycle of such batteries. They found that Zn passivahon is the main factor of the life cycle of zinc-polyaniline batteries. In recent times [359], zinc-poly(anihne-co-o-aminophenol) rechargeable battery was also studied. Other types of batteries based on zinc were of some interest [360]. 

In modem commercial lithium-ion batteries, a variety of graphite powder and fibers, as well as carbon black, can be found as conductive additive in the positive electrode. Due to the variety of different battery formulations and chemistries which are applied, so far no standardization of materials has occurred. Every individual active electrode material and electrode formulation imposes special requirements on the conductive additive for an optimum battery performance. In addition, varying battery manufacturing processes implement differences in the electrode formulations. In this context, it is noteworthy that electrodes of lithium-ion batteries with a gelled or polymer electrolyte require the use of carbon black to attach the electrolyte to the active electrode materials.49-54 In the following, the characteristic material and battery-related properties of graphite, carbon black, and other specific carbon conductive additives are described. 

Needless to say that a deep understanding of both the formation mechanism of the SEI layer and the underlaying question of carbon s surface chemistry in a particular electrolyte solution is of utmost importance for battery developers. Clearly, the surface chemistry of graphite electrodes plays a key role in their performance.259 312 325 343-352 A lot of work was devoted to decipher this very complicated surface chemistry. It is therefore not surprising that the advancement in the understanding of surface chemistry of carbon electrodes in nonaqueous electrolytes correlates well with the worldwide production rate of lithium-ion batteries. 

Similar to the behavior of nonactive metal electrodes described above, when carbon electrodes are polarized to low potentials in nonaqueous systems, all solution components may be reduced (including solvent, cation, anion, and atmospheric contaminants). When the cations are tetraalkyl ammonium ions, these reduction processes may form products of considerable stability that dissolve in the solution. In the case of alkali cations, solution reduction processes may produce insoluble salts that precipitate on the carbon and form surface films. Surface film formation on both carbons and nonactive metal electrodes in nonaqueous solutions containing metal salts other than lithium has not been investigated yet. However, for the case of lithium salts in nonaqueous solvents, the surface chemistry developed on carbonaceous electrodes was rigorously investigated because of the implications for their use as anodes in lithium ion batteries. We speculate that similar surface chemistry may be developed on carbons (as well as on nonactive metals) in nonaqueous systems at low potentials in the presence of Na+, K+, or Mg2+, as in the case of Li salt solutions. The surface chemistry developed on graphite electrodes was extensively studied in the following systems ... 

The wide variety of Li-Ion battery chemistries is discussed in the following section "Lithium batteries" M= (La,Ce,Nd,Pr)(Ni,Co,Mn,AD5 alloy... 

Refs. [i] Besenhard, Sitte W (2001) Electroactive materials. Springer, Wien, p 129 [ii] Dell RMJ, Rand DA (2001) Understanding batteries. Royal Society of Chemistry, London, p 264 [Hi] Nazri GA, Pistoia G (eds) (2003) Lithium batteries science and technology. Springer, Boston, p 344 [iv] Van Schalkwijk W, Scrosati B (eds) (2002) Advances in lithium-ion batteries. Springer, Berlin p 524... 

There are two main kinds of rechargeable battery based on lithium chemistry the lithium-metal and the lithium-ion battery. In both the positive electrode is a lithium insertion material the negative in the former is lithium metal and in the latter it is a lithium insertion host. The reason for the application in lithium batteries of insertion electrode materials, which are electronic and ionic conductive solid matrixes (inorganic and carbon-based), is that electrochemical insertion reactions are intrinsically simple and highly reversible. 

There are two types of electrodes, metal electrodes and porous electrodes. For instance, lithium-ion batteries possess porous electrodes (as shown in Fig. 1), while lead-acid batteries have metal electrodes. The selection between metal and porous electrodes depends on the chemistry and on the safety of the battery. Porous electrodes in a battery are usually very thin to reduce the internal resistance of the battery. They are typically made of small particles to reduce internal diffusion limitations and to provide a large... 

Beguin, F., ChevaUier, F., Letellier, M., et al. (2006). Mechanism of reversible and irreversible insertion in nanostructured carbons used in lithium-ion batteries. In New Carbon Based Materials for Electrochemical Energy Storage Systems, NATO Science Series, Mathematics, Physics and Chemistry, Springer, Dordrecht The Netherlands, 229, 231-43. 

Depending on the application and the battery chemistry, the functions within the tasks are different. For small batteries, some of the Ksted functions are available as single- or multiple-chip solutions. For example, lithium-ion battery packs for cellular phones and laptop computers contain, as a minimum, a safety-management function. In the case of larger battery systems, the BMS is more complex and must be individually developed for the battery technology and the application. 

The intercalation and deintercalation chemistry of the LiM02 (M = Ni, Co) phases forms the basis for the operation of lithium-ion batteries and is discussed in more detail in Section 3.7.1. Sodium ions also can be deintercalated from the host lattices Naj M02 (M = Ti, Cr, Mn, Co, Ni) by electrochemical oxidation but the electrochemical behavior is very complicated. Limited ranges of solid solution and large numbers of intermediate phases are observed. 

Y. Yang, Z. Zhang, Z. Gong, Electrochemical performance and surface properties of bare and Ti02-coated cathode materials in lithium-ion batteries . Journal of Physical chemistry B, 108(45), 17546-17552, (2004). 

Thackeray, M.M, C.S, Johnson, J.T, Vaughey, N. Li, and S.A. Hackney, Advances in manganese-oxide composite electrodes for lithium-ion batteries. Journal of Materials Chemistry, 2005, 15(23) pp, 2257-2267... 

---