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Battery calorimeter

A simpler and more elegant way to compensate either exothermic or endothermic effects was used by Dzhigit et al. in 1962 [42], A Joide effect is produced in the system and this is controlled to ensure a constant temperature difference (say, 5 K) between the system S and the thermostat T and, hence, a constant heat-flow. If the phenomenon studied is endothermic, the Joule effect is automatically increased to ensure the constant heat flow required. If it is exothermic, the Joule effect is simply decreased. These changes in the Joule effect are recorded and provide a direct measurement of the heat involved in the phenomenon studied. This was also used by Hansen et aL in 1982 in their high temperature battery calorimeter [43]. [Pg.36]

NREL (2011) Large-Volume Battery Calorimeter, National Renewable Energy laboratory. Available at http //www.mel.gov/ vehiclesandffiels/energystorage/pdls/50558. pdf (September 22, 2011). [Pg.221]

The experimental techniques described above of charge—discharge and impedance are nondestructive. Tear-down analysis or disassembly of spent cells and an examination of the various components using experimental techniques such as Raman microscopy, atomic force microscopy, NMR spectroscopy, transmission electron microscopy, XAS, and the like can be carried out on materials-spent battery electrodes to better understand the phenomena that lead to degradation during use. These techniques provide diagnostic techniques that identify materials properties and materials interactions that limit lifetime, performance, and thermal stabiity. The accelerated rate calorimeter finds use in identifying safety-related situations that lead to thermal runaway and destruction of the battery. [Pg.12]

Robert Wilhelm Bunsen, 1811-1899, German chemist who investigated the cacodyl radical, the geysers of Iceland, and the chemical action of light. Inventor of the Bunsen battery, the grease-spot photometer, ice and vapor calorimeters, the thermoregulator, the constant-level water-bath, and the filter pump. [Pg.618]

Electrochemical calorimetry — is the application of calorimetry to thermally characterize electrochemical systems. It includes several methods to investigate, for instances, thermal effects in batteries and to determine the -> molar electrochemical Peltier heat. Instrumentation for electrochemical calorimetric studies includes a calorimeter to establish the relationship between the amount of heat released or absorbed with other electrochemical variables, while an electrochemical reaction is taking place. Electrochemical calorimeters are usually tailor-made for a specific electrochemical system and must be well suited for a wide range of operation temperatures and the evaluation of the heat generation rate of the process. Electrochemical calorimeter components include a power supply, a device to control charge and discharge processes, ammeter and voltmeter to measure the current and voltage, as well as a computerized data acquisition system [i]. In situ calorimetry also has been developed for voltammetry of immobilized particles [ii,iii]. [Pg.186]

On the other hand, for slow reactions, adiabatic and isothermal calorimeters are used and in the case of very small heat effects, heat-flow micro-calorimeters are suitable. Heat effects of thermodynamic processes lower than 1J are advantageously measured by the micro-calorimeter proposed by Tian (1923) or its modifications. For temperature measurement of the calorimetric vessel and the cover, thermoelectric batteries of thermocouples are used. At exothermic processes, the electromotive force of one battery is proportional to the heat flow between the vessel and the cover. The second battery enables us to compensate the heat evolved in the calorimetric vessel using the Peltier s effect. The endothermic heat effect is compensated using Joule heat. Calvet and Prat (1955, 1958) then improved the Tian s calorimeter, introducing the differential method of measurement using two calorimetric cells, which enabled direct determination of the reaction heat. [Pg.236]

As his research advanced to the studies of gases and alkali metals, Bunsen recognized the importance of developing new methods to analyze and identify chemical substances. The importance of quantitative analysis was realized in the late eighteenth century. Chemists needed to probe further into a substance s composition in order to help explain the physical world. Bunsen recognized this need and worked to develop new instruments for this purpose. For example, he invented new types of galvanic and carbon-zinc electrochemical cells, or batteries, to isolate barium and sodium. He also constructed a new type of ice calorimeter that measured the volume, rather than the mass, of melted water. This allowed Brmsen to measure a metal s specific heat in order to find its atomic weight. [Pg.178]

In some of his experiments. Joule used electrical work rather than mechanical work. To achieve the same effect as in Problem 2.4(a), for what duration would electrical work have to be provided to the calorimeter, if the current originated from a 100-volt battery and it encountered a 1000-ohm resistance ... [Pg.65]

Measuring thermal parameters of Li-ion cells is crucial for optimizing the thermal design of battery systems with respect to lifetime and safety issues. The thermal parameters of interest are heat capacity, thermal conductivity, and heat exchange between the cell s surface and the environment due to radiation and convection. Traditionally, heat capacity is obtained by calorimeter measurements and thermal conductivity is obtained by heat flux or Xenon-Flash measurements [1], Disadvantages of these methods are the requirement of expensive measurement devices and the destruction of the cell for thermal conductivity measurements. [Pg.39]

An unusual large isoperibol calorimeter serves to measure the heat production of large car batteries under real loading and unloading conditions. The calorimeter chamber (40 x 60 x 40 cm ) is lar enough to contain not only test cells and... [Pg.172]

Gnanaraj et al. (2003) measured both pressure and temperature rises during the decomposition reactions of electrolyte solutions for Li-ion batteries in a commercial ARC calorimeter in the temperature range 40-350 °C. Among other results, an explosion was observed with lithium perchlorate solution near 220 °C. [Pg.216]

A simple calorimeter to measure the heat developed on mixing liquids or solids. Thermal battery analyzer To measure the heat production on loading and controlled unloading of batteries. [Pg.217]

The problems of energy measurement in adiabatic calorimetry have been discussed (see ref. 3). Storage batteries previously used as a source of power for the calorimeter heater can now be replaced by very stable... [Pg.137]

Calorimetry methodology is important for the design and testing of inherendy safer batteries. Table 5 displays the testing needs of battery via various calorimeters. Once the properties of the cell components are known then the components need to be evaluated in combination with each other. An adiabatic calorimeter is often used when conducting multiphase compatibility studies. Testing full cells is an important aspect of battery safety evaluation, that include,... [Pg.433]

Table 5 Battery safety testing needs by various calorimeters... Table 5 Battery safety testing needs by various calorimeters...
Wang Q, Sun JH, Yao XL, Chen CH (2006) Micro calorimeter study on the thermal stabihty of lithium-ion battery electrolytes. J Loss Prev Process Ind 19 561-569... [Pg.453]

Combustion reactions are studied in a bomb calorimeter of constant volume. Electric battery driving motors... [Pg.100]

There yawns a large gap between commercial (micro)calorimeters with maximum vessel volumes of 25, 30 or 100 mL and instruments of many litres for smaller domestic animals. The only exception known to the authors is the Seta-ram GF 108 1-L instrument used in the Leyden group [72]. A low-price solution for an intermediate size calorimeter was found in cooling/warming boxes sold as picnic equipment for less than US 200 [73], They are equipped with a Peltier battery as a heat pump between the inner volume of the box and the environment. In the same way the heat pump can work as a Seebeck heat flow sensor to determine heat production rates inside the box. The inner walls of the box may be additionally covered by copper foil of high thermal conductivity to facilitate heat flow to the sensor. [Pg.421]


See other pages where Battery calorimeter is mentioned: [Pg.172]    [Pg.172]    [Pg.1918]    [Pg.625]    [Pg.208]    [Pg.94]    [Pg.700]    [Pg.700]    [Pg.1918]    [Pg.541]    [Pg.219]    [Pg.62]    [Pg.691]    [Pg.106]    [Pg.173]    [Pg.867]    [Pg.431]    [Pg.435]    [Pg.440]    [Pg.443]    [Pg.290]    [Pg.419]    [Pg.423]   
See also in sourсe #XX -- [ Pg.36 ]

See also in sourсe #XX -- [ Pg.160 ]




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