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Lithium-ion battery (Li-ion Batteries) developed from a lithium battery dell BAT3151L8 battery . Therefore, introducing the Li-ion, before introducing lithium batteries. For example, previously used button batteries inside the camera belongs to Li-ion battery. Lithium battery cathode material is manganese dioxide, or thionyl chloride, lithium anode. After the completion of the battery assembly that is the battery voltage, without charge. Such cells may also be charged, but the cycle performance is not good, in the charge-discharge cycle, the easier the formation of lithium dendrite, causing internal short-circuit the battery, so under normal circumstances in which such the battery charging is prohibited. Later, Japan's Sony Corporation has come to carbon materials as the anode, lithium-containing compounds in order to make positive, in the charge-discharge process, there is no lithium metal, and only lithium-ion, which is lithium-ion battery. When charging the battery when the battery on the positive lithium ion generation, resulting lithium-ion movement through the electrolyte to the cathode. As the carbon anode layered structure, it has a lot of micro, to lithium-ion on the anode embedded in porous carbon layer, the embedded lithium-ion the more the higher the charge capacity. Similarly, when the battery discharge (ie, the process we use the battery), embedded in the carbon cathode layer of lithium-ion extrusion, but also movement back to positive. Back to the cathode of lithium-ion the more the higher discharge capacity. We usually say that the battery capacity is the discharge capacity. In the Li-ion charge-discharge process, lithium-ion transition from the positive → negative → positive moves in space. Li-ion Batteries is like a rocking chair, rocking chair at both ends of the battery poles, while the lithium-ion rocking back and forth as players do run. Therefore, Laptop Battery Li-ion Batteries also known as rocking chair batteries.
Integral part of the lithium-ion battery cells
Steel / aluminum Series:

(1) battery cover from top to bottom

(2) positive - active substances usually lithium cobalt oxide

(3) diaphragm - a special kind of composite membrane

(4) negative - active substances for the carbon

(5) Organic electrolyte

(6) Battery shell (divided into two kinds of steel and aluminum)

Flexible Series

(1) positive - active substances usually lithium cobalt oxide

(2) diaphragm - PP or PE composite film

(3) negative - active substances for the carbon

(4) Organic electrolyte

(5) Battery shell - aluminum composite films
Charge
The first charge, if time can be longer, then the electrode as much as possible to the highest oxidation state, and so be able to increase battery life.
Advantages and disadvantages of lithium-ion battery
Lithium-ion battery dell 1G222 battery has the following advantages:

1) Voltage high, single battery voltage of up to 3.6-3.9V, is a Ni-Cd, Ni-H batteries 3 times

2) than the energy larger than the present to achieve real energy 100-125Wh/kg and 240-300Wh / L (2 times higher than Ni-Cd, 1.5 times higher than Ni-MH), the future, as technological development, specific energy can be Up to 150Wh/kg and 400 Wh / L

3) The long cycle life in general can reach more than 500 times, or even 1000 times or more. For a small electrical current discharge, the battery will double the lifespan of electrical appliances competitiveness.

4) The safety performance is good, pollution-free, no memory effect. As the predecessor of Li-ion batteries, due to the formation of lithium dendrite easy to short-circuit, reducing its application areas: Li-ion does not contain cadmium, lead, mercury, etc. elements of the environment pollution: Some processes (such as sintered) and Ni-Cd batteries there is a major drawback for the "memory effect", seriously hindered the use of batteries, but Li-ion dell INSPIRON 2650 battery does not exist at this problem.

5) The self-discharge is small, full of electricity at room temperature Li-ion storage a month after the self-discharge rate of about 10%, much lower than Ni-Cd of 25-30%, Ni, MH 30-35%.

6) can quickly charge and discharge, 1C charge is the capacity can reach more than 80% of the nominal capacity.

7) The operating temperature range and high operating temperature of -25 ~ 45 ° C, with the electrolyte and the positive improvements, hoping to broaden the -40 ~ 70 ° C.

Lithium-ion batteries also exist some disadvantages, such as:

1) The high cost of batteries. Mainly reflected in the price of LiCoO2 cathode materials for high-(Co fewer resources), electrolyte purification system difficult.

2) can not be high-current discharge. As the organic electrolyte system, and other reasons, the battery internal resistance compared to other type of batteries dell INSPIRON 2600 battery big. Therefore, I demand a smaller discharge current density, the discharge current at 0.5C below normal, only suitable for small and medium-current electrical use.

3) The need to protect the line control.

A, overcharge protection: Battery over charge would undermine the positive structure, which affects the performance and life; the same time, the overcharge to the electrolyte decomposition, excessive internal pressure caused by leakage and other problems; and therefore must be under constant pressure 4.1V-4.2V charge;

B, over-discharge protection: over-discharge recovery of active substances will lead to difficulties, they also need protection circuit control.

Abstract: The development trend of lithium ion batteries, lithium-ion battery outlined mechanism of charging and discharging situation of theoretical studies, summarized as the core technology of the lithium battery positive and negative electrode material prepared by the existing theory and recent developments, review of the cathode materials and anode materials for a variety of preparation methods and prospects for development, highlighting the current problems and improvements in the field dell 312-0292 battery development.
Materials
Electronic information age, so that the mobile power needs are growing rapidly. As the lithium-ion battery with high voltage, an important advantage of high capacity and long cycle life, safety performance is good, so that the portable electronic devices, electric vehicles, space technology, defense industry, and many have broad application prospects, becoming the last few years of extensive public attention in research focus. The mechanism of lithium-ion battery general analysis that the lithium-ion battery as a chemical power source, refer to two separate and de-embedding can be reversibly lithium intercalation compounds as positive and negative ion secondary battery constituted. When the battery is charging, the lithium-ion from the cathode in the de-embedded, embedded in the cathode, discharge the contrary. Lithium-ion battery is physics, materials science and chemistry of the crystallization of interdisciplinary research. Lithium-ion batteries involved in the physical mechanism, is currently being embedded in solid-state physics to explain the physical, the embedding (intercalation) is movable object particles (molecules, atoms, ions) reversible embedded in the main body with the right size of the lattice The network space point. Electron transport lithium-ion battery cathode and anode materials are mixed ionic and electronic conductor embedded compound. Electronics can only be positive and negative material movement [4] [5] [6]. Embedded in a wide range of known compounds, object particles can be molecules, atoms or ions. In the embedded ions, requested by the main structure for charge compensation in order to maintain electrical neutrality. Charge compensation can be the main material can be achieved with changes in the structure, electrical conductivity before and after the embedded subject to change. Lithium-ion battery electrode materials can exist stably in the air is closely related with this feature. Intercalation compound only to meet the structural changes in reversible and are able to change the structure in order to compensate for the charge, as dell Inspiron 2200 battery lithium-ion battery electrode materials.

Control the performance of lithium-ion batteries key material - Battery Chiang Kai-shek negative active material is the key to this technology, it is the consensus of the researchers at home and abroad.

A cathode material performance and the general preparation method

Positive characterization of ion transport in the nature of the important parameter is the chemical diffusion coefficient, usually, the positive active material in lithium-ion diffusion coefficients are relatively low. Cathode materials for lithium insertion into or from the working-class de-embedded material, accompanied by changes in crystal phase. Therefore, the lithium-ion batteries require a very thin film electrodes, usually tens of microns in order of magnitude. Cathode Material Lithium compounds are lithium-ion battery Lithium-ion temporary storage containers. In order to obtain a high single battery voltage, tend to choose high electrical potential of the lithium dell Inspiron 1000 battery intercalation compounds. Cathode material should be met:

1) In the required charge-discharge potential within the electrolyte solution has the electrochemical compatibility;

2) moderate kinetics of electrode process;

3) a high degree of reversibility;

4) full of state of lithium in the air stability.

The study focused on layered LiMO2 hot and spinel-type structure of compounds and composite LiM2O4 two kinds of M (M is Co, Ni, Mn, V and other transition metal ions) is similar to the electrode materials. As a lithium-ion battery cathode material, Li + ions in the process of de-embedding and embedding structural changes in the extent and reversibility determine the stability of the battery charge and discharge of repetition. Preparation of cathode material, its material properties and synthesis of process conditions will have an impact on the final structure. A variety of promising cathode material, there is the use of the cycle of decay in capacitance, which is a research priority. Have been commercialized cathode materials Li1-xCoO2 (0
1) solid-phase method generally used in lithium carbonate and other lithium salts and cobalt or nickel compounds, lapping compounds, after mixing to sintering reaction [10]. Advantage of this method is to process simple and easy to get raw materials belonging to the early development of lithium-ion battery development and production has been extensively studied approach, the more mature foreign technology; disadvantage is that the prepared cathode materials for electric capacity is limited, poor mixing of raw materials, preparation of materials performance, stability, good, quality, consistency between batches and the batch difference.

2) The complex method using organic complex preparation containing the first lithium-ion and cobalt or vanadium ion complex precursor, and then sintering. This method has the advantage of molecular-scale mixing, material uniformity and performance, good stability, cathode materials, high capacitance compared to solid-state method, and foreign has been testing lithium-ion batteries used for the industrialization of methods, technologies not mature, yet few reported.

3) sol-gel method using the last century, 70 years since the development of

Preparation of ultrafine particles to the method of preparation of cathode material, the method has the advantages of the complex law, but also prepared the dell TD347 battery capacitance of the electrode materials have a greater increase being at home and abroad belong to the rapid development of methods. The disadvantage is high cost of technology is a development stage [11].

4) ion exchange process such as Armstrong prepared by using ion-exchange LiMnO2, won the reversible discharge capacity of 270mA · h / g high-value, this method for studying the new hot spot, which has the electrode system, stable performance, high capacity electrical characteristics of . However, re-crystallization process involves evaporation of solution and time-consuming steps such as license fees, there is a considerable distance away from practical use.

Cathode materials research literature can be seen from abroad, its power capacity to an annual 30 ~ 50mA · h / g at the rate of growth and development tend to become smaller and smaller-scale micro-structure, while increasing power capacity of lithium intercalation compounds and raw materials to the nano-scale advance, on the structure of lithium intercalation compounds, theoretical research has made some progress, but its development in the theory is still evolving. Trouble in this area increases the capacity of lithium battery dell KD476 battery power and recycling capacity fade problem, researchers have proposed to add other components to overcome the method [12] [13] [14] [15] [16] [17]. But for now, these methods have not thoroughly studied the theory of the mechanism, leading Japanese scholars Yoshio.Nishi that in the past decade, little substantive progress in this field [1], an urgent need for further study.

2 Anode material properties and the general preparation method

The conductivity of anode materials are generally higher, select potential as close as possible potentials can be embedded lithium-lithium compounds, such as various carbon materials and metal oxides. Reversibly de-embedded embedded anode material for lithium-ion requires:

1) In the lithium-ion intercalation reaction in the free energy change is small;

2) lithium-ion solid-state structures in the anode have a high proliferation rate;

3) highly reversible intercalation reaction;

4) have a good electrical conductivity;

5) The thermodynamic stability, while not react with the electrolyte.

Research focused on carbon materials and has a special structure of other metal oxides. Graphite, soft carbon, medium-carbon microspheres have been in the country there are development and research, hard carbon, carbon nanotubes, buckyballs C60 and other carbon materials is dell GD761 battery being studied in [18] [19] [20] [21] [22] [23]. Japan's Honda Researchand Development Co. , Ltd, K. Sato and other people use poly p-phenylene vinylene (Polyparaphenylene - PPP) of thermal decomposition products PPP-700 (to a certain heating rate heating PPP to 700 ℃, and the heat some time to be a product of the pyrolysis) as a negative, the reversible capacity of up to 680mA · h / g. U.S. MIT, MJMatthews reports PPP-700 lithium storage capacity (Storagecapacity) up to 1170mA · h / g. If the lithium storage capacity of 1170mA · h / g, with an increase in the amount of lithium insertion, thereby improving lithium-ion battery performance, I believe that future research will focus on the smaller nano-scale micro-structure of lithium intercalation. Study of carbon anode is almost the same time, looking for potential and Li + / Li potential similar to other anode material has been taken seriously. Lithium-ion batteries used in the carbon materials surviving in two aspects:

1) Voltage lags, that is, lithium intercalation reaction in between 0 ~ 0.25V (relative to Li + / Li) and the de-embedded response occurred at about in the 1V;

2) Cycle the capacity decreased gradually, generally after 12 to 20 cycles, the capacity dropped to 400 ~ 500mA · h / g.

Theory also relies on the further deepening of a variety of high-purity, structural regularity of raw materials and carbon materials Preparation and Characterization of a more effective method of building. Fuji has developed a new type of lithium-ion battery anode materials for tin-based composite oxide, in addition to the existing research has focused on a number of metal oxides, the mass ratio of energy than the carbon anode materials increased substantially. Such as SnO2, WO2, MoO2, VO2, TiO2, LixFe2O3, Li4Ti5O12, Li4Mn5O12, etc. [24], but not as sophisticated carbon electrode. Lithium in carbon materials, reversible high-storage mechanism in the main formation mechanism of lithium Li2 molecule, multi-layered lithium mechanism, mechanism of crystal lattice, elastic ball - elastic net model, layer - side-side - the surface of lithium storage mechanism of nano-graphite reservoir Li-ion mechanism, carbon - lithium - lithium hydrogen storage mechanism and the mechanism of pore. Graphite, as a kind of carbon materials, has long been found that it formed with the lithium-graphite intercalation compound (Graphite Intercalation Compounds) LiC6, but these theories is still in development stage. To overcome the difficulties of anode materials is also a question of capacity loop attenuation, but in literature we can see that preparation of high purity and regularity of the micro-structure of carbon anode materials is the dell Inspiron E1505 battery development of a direction.

Preparation of anode materials for the general method can be summarized as follows.

1) In a certain high temperature heating of soft carbon highly graphitized carbon; embedded lithium-ion graphite compound formula is LiC6, in which the lithium ions in graphite the process of embedding and de-embedding dynamic changes of the graphite structure and electrochemical properties of the relationship between Irreversible capacity loss of the causes and improve the way such issues have been a number of researchers have explored. 2) will have a special structure, cross-linking resin under high temperature decomposition of the hard carbon, graphite reversible capacitance than high, its structure influenced by the raw materials, but the general literature that these carbon nano-pore structure of its embedding Lithium capacity will have significant impact on their studies have focused primarily on the use of a special molecular structure of the polymer to prepare with more of hard nano-porous carbon [25] [26] [27].

3) High temperature thermal decomposition of organic compounds and polymers prepared by hydrogen-carbon [28] [29]. Such materials have 600 ~ 900mA · h / g reversible electric capacity, and thus have attracted attention, but its voltage drop lag and recycling capacity is at issue is the biggest obstacle to application. An improved method for its preparation and theories to explain the mechanism will be the focus of the study.

4) All kinds of metal oxide and its mechanism is similar with the cathode material [24],

Has also been the attention of researchers to study the main aim is to obtain a new structure or composite structure of metal oxides.

5) as a lithium intercalation material, carbon dell Inspiron 6400 battery nanotubes, buckyballs, etc. C60 is also the current research, a new hot spot has become a branch of nano-materials research. Carbon nanotubes, the special structure of C60 buckyballs make it into a high-capacitance materials, the best choice for lithium insertion [22] [23] [30]. In theory, the availability of embedded nano-structured lithium capacity than currently available materials must be high, the micro-structure has been studied extensively and have made great progress, but how to prepare an appropriate way to achieve excellent stacking performance electrode material, this should be an important direction of research [31] [32] [33].

3 Conclusion

To sum up, in recent years, lithium-ion battery cathode active materials Chiang Kai-shek research and development and application, is very active in the international arena, and has made great progress. The crystal structure of structured materials, charge-discharge process of irreversible changes in the structure does not occur is to obtain a high specific capacity, long cycle life of lithium-ion batteries key. However, lithium intercalation materials, structure and properties of the field is still currently the weakest link. Lithium-ion battery research is a kind of continuously updated battery system, a lot of physics and chemistry of new lithium-ion battery research will have a major impact, such as nano-solid electrodes, it is possible to make lithium-ion batteries have higher energy density and power density, thereby greatly increasing the lithium-ion battery applications. In short, lithium-ion battery research is a matter of chemistry, physics, materials, energy, electronics and many other disciplines, cross-cutting areas. The current progress in this area has given rise to the power sector and the chemical industry with great interest. Can be expected, as the relationship between structure and properties of electrode materials in-depth study, from the molecular level, designed for a variety of structured doping composite structure or the structure of positive and negative materials will be a strong impetus to lithium-ion battery research dell Inspiron 8600 battery and applications. Lithium-ion batteries will be following the nickel-cadmium, nickel-metal hydride batteries, after a fairly long period of time in the future, the market prospects for the best and the fastest growing of a secondary battery.