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The Lithium ion battery is the preferred source of power for many wireless and portable consumer products. A typical battery pack with lithium ion cells features a variety of active and passive safety devices and protection circuitry to prevent or mitigate potential cell failures. One of the passive safety components in a lithium ion cell is the cell-can's mechanical safety vent, which is intended to release the internal pressure of the cell when a specified pressure is reached, but prismatic cells swell and cylindrical cells bulge during pressurization. It is therefore, desirable to test the cell's venting mechanism in a controlled manner in order to ensure that both the cell's can and the performance of the safety vent is not compromised and that the results are not skewed by the test method. A suitable test setup should not inhibit the natural expansion of the cell's can during the test. This paper discusses the various venting mechanisms employed by prismatic and cylindrical lithium ion cells and test methods to characterize the mechanical safety vent's opening pressure for both cylindrical and prismatic cells Slide-In Battery Contacts Economical contacts are designed to "slide-in" to the battery compartment of electronic equipment. Coil spring contacts are designed with a unique spring tension ability and they accurately adjust to variations in battery length. Snap-In Battery Contacts Economical and reliable battery contacts, consisting of leaf spring, coil spring and button type designs, is ideal for use with electronic products having molded-in battery compartments. Thru-Hole Battery Contacts Button and Spring contacts are ideal for top-side board mounting in PCB packaging applications Surface Mount Battery Contacts Button and Spring contacts are ideal for top-side board mounting in PCB packaging applications. Supplied in Bulk or on tape and reel About Batteries o How Do Batteries Work? o Battery History o Battery Care o Battery Leakage o FAQ Ever wonder how that little battery powers your favorite devices? We give you an inside look at how alkaline batteries work. You can think of a battery as a small power plant that converts a chemical reaction into electrical energy. Various dry cell (or alkaline) batteries can differ in several ways, but they all have the same basic components. Battery Parts Container A steel can housing the cell’s ingredients to form the cathode, a part of the electrochemical reaction. Cathode Manganese dioxide mixture and carbon. Cathodes are the electrodes reduced by the electrochemical reaction. Separator A non-woven, fibrous fabric that separates the electrodes. Anode Powered zinc metal. Anodes are the electrodes that are oxidized. Electrodes Where the electrochemical reaction takes place. Electrolyte A potassium hydroxide solution in water. The electrolyte is the medium for the movement of ions within the cell and carries the iconic current inside the battery. Collector A brass pin in the middle of the cell that conducts electricity to the outside circuit. 1 2 3 4 5 6 7 Constructing The Battery Container It all starts with an empty steel can – the battery container. Cathode Mix A cathode mix – finely ground powders of manganese dioxide and conductors carrying a naturally-occurring electrical charge – is molded to the inside wall of the empty container. Separator A separator paper is inserted to keep the cathode from touching the anode. Separator A separator paper is inserted to keep the cathode from touching the anode. Anode The anode, which carries a negative electrical charge, and potassium hydroxide electrolyte are then pumped into each container. Collector The brass pin, which forms the negative current collector, is inserted into the battery which, is then sealed and capped. 1 2 3 4 5 6 Powering The Device Chemical Reacts 00146780252224 FORID:10 UTF-8 In This Section Battery Anodes Battery Cathodes Depletion Aggregation Membranes BATTERY ANODES Introduction The anode is the negative electrode of a primary cell and is always associated with the oxidation or the release of electrons into the external circuit. In a rechargeable cell, the anode is the negative pole during discharge and the positive pole during charge. Lithium Anode The anode in the battery deserves an equal say in the overall performance of a battery. For an effective development of a high energy density battery, the use of high capacity electrode materials (anode& cathode) is an essential factor. For such systems, alkali metals are perhaps the obvious choice. The most promising types of advanced batteries currently under production are based on lithium anodes. The choice of the anode material is very much restricted by the need for a high energy content, which is unavoidably linked, to the use of an alkali metal as the main anode material.Lithium is generally preferred, since it can be more easily handled (though with care) than other alkali metals and more significantly, the lightest and the most electropositive among the alkali metal family. Also, the low density of lithium metal (0.534g/cc) leads to the highest specific capacity value of 3.86Ah/g, which stands exceptional. Therefore, lithium batteries possess the highest voltage and energy density of all other rechargeable batteries and are therefore favored in applications related to portable appliances where low weight and small volume are the major constraints. The advantages of using lithium metal as the anode are as follows: Good reducing agent Highly electropositive(so higher voltage is obtained depending upon the cathode used) High electrochemical equivalence High capacity (3.82Ah/g) and energy density (1470Wh/Kg) Good conducting agent Good mechanical stability Ease of fabrication/compact design The essential reaction of metallic lithium anode is very simple: But, in spite of this simplicity, the practical application of Li metal to a rechargeable anode has been very difficult due to some crucial issue. The most important one is that Li metal usually will tend to deposit as a dendrite or mossy structure during charge, and the disordered metallic deposit gives rise to a poor coulombic efficiency. This happens because such a fine Li metal often acts as an active site inducing reductive decomposition of electrolyte components. Part of the deposit may become electrically isolated and shedding may also occur. Furthermore, the fine metallic lithium may easily penetrate into the separator and eventually cause internal short, this resulting in heat generation and contingent ignition. One of the main reasons for the failure of rechargeable lithium systems lies in the reactivity of lithium with electrolytes]. Hence the hazardous nature of Li has paved way to identify some other safer anode materials, possessing comparably the same electrochemical features as that of lithium. Alternate anodes for lithium batteries Carbonaceous materials, which allow the intercalation of Li within the layers, are clearly the most suitable candidates, leading to the popularly known lithium-ion or shuttlecock or Lithium Rocking Chair Batteries (RCB). Most carbon varieties including graphite are gaining importance as attractive candidates of anode materials for rechargeable lithium batteries, because they can accommodate lithium reversibly and offer high capacity, good electronic conductivity and low electrochemical potential (with respect to Li metal). The maximum amount of lithium that can be intercalated within the graphite structure is 1 per 6 carbon atoms, yielding a specific capacity of 372mAh/g. The cost, availability, performance and potential (vs. Li metal) of carbon-based materials are all acceptable and even preferable when compared to lithium metal anode for practical cells. An important evidence for this is the commercial availability of LiCoO2/carbon cells manufactured by Sony Inc. There is no significant swelling of, or stack pressure generation by the carbon electrode on prolonged cycling and therefore Li-ion cells can be constructed as flat or prismatic cells with thin-walled cases or in any other cell configurations. The shortcomings on the deployment of different types of anode materials are displayed in Table 1 MATERIAL REMARK LITHIUM DENDRITE GROWTH, EXPENSIVE, TOXIC CARBON IRREVERSIBLE CAPACITY LOSS TIN INCLUSION OF SOLID ELECTROLYTE PHASE IN THE ELECTRODE ATCO COMPLICATED LITHIUM UPTAKE/REMOVEL M-M ALLOY LARGER VOLUME CHANGES (MECHANICAL DECRIPITATION) TERNARY METAL VANADATES ARGUABLE Li DIFFUSION MECHANISM METALLOIDS MOISTURE SENSITIVE Hollow Fe3O4 Nano materials as anodes Figure 1. The current work investigates the potential for hollow nanostructures to mitigate the pulverization problem and fast capacity fading for anode materials in lithium-ion batteries (LIBs). Hollow Fe3O4 nanoparticles are synthesized via a template-free solvothermal method using FeCl3, urea and ethylene glycol as starting materials. Temporal XRD and TEM (Figure 1) studies indicate that the growth follows an inside-out Ostwald ripening mechanism. Higher concentrations of urea in the starting material result in lower percentages of hollow particles (phi) and this observation is consistent with the proposed growth mechanism. The performance of the hollow particles as anode materials in LIBs is tested and shown to be superior to their solid counterparts, Figure 2. with higher percentages of hollow particles giving better performance (Figure 2), which provides evidence for the hypothesis that hollow structures are able to alleviate the pulverization problem. Cyclic voltammograms of Fe 3O4 nanoparticles are analyzed which provides some insight into the reaction mechanism of the lithium-ion insertion/deinsertion process.