Battery management thermal, electrical systems

Battery pack development for electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) includes many of the same considerations involved in the development of battery packs for hybrid electric vehicles (HEVs). Typical Li-ion battery packs, also called rechargeable energy storage systems (RESS), generally include four main components (1) lithium-ion battery cells, (2) mechanical structure and/or modules, (3) battery management system (BMS) and electronics, and (4) thermal management system. 

LIBs are integrated in the electric drivetrains with electric motors/generators, power conversion units (inverters), and power monitoring and control electronics to ensure safe and smooth bus operation. The PMS includes hardware and software for the battery management system (BMS) and the thermal management system (TMS) that monitor... 

This cell system is also under active development for EV traction. Realistic targets are reported as 80 Wh/kg for energy density, 200 W/kg for power density, and a cycle life of over 1000. The Ovonic Battery Co have already demonstrated 67 Wh/kg for a 250 Ah battery, and Panasonic have reported a similar value for a 130 Ah unit. Thermal management and cost are likely to be the key factors limiting development of nickel-metal hydride technology for electric vehicles. 

Electrochemical cells, for example, photoelectrochemical cells, batteries, fuel cells, or supercapacitors, consist of assemblies of functional electrode and electrolyte layers. Individual cells are linked together electrically to form stacks, whereas stacks form part of energy systems, that involve additional units for fuel storage, thermal management, and so on. The development of energy systems is thus a hierarchical and cross-disciplinary exercise, with strongly coupled phenomena arising across multiply connected structural levels. 

A novel thermal management system for electric vehicle batteries using phase-change material. /. Ekctrochem. Soc., 147 (9), 3231-3236. 

Lithium-ion battery packs generally consist of modules coupled in series and/or parallel, and modules in turn consist of series and/or parallel coupled cells. The assembly process is shown schematically in Figure 14.13. In addition, lithium-ion battery packs also include charge and discharge controllers, a thermal management system, a module balance electronic system, and an electronic system to communicate with the outside (such as electric vehicles). Due to the very large capacity, lithium-ion battery packs have... 

Micro fuel cell system faces numerous challenges for its widespread application in mobile devices. The electrical interfaces and the size of the fuel cell system should be maintained same as that of batteries. Fuel cells lack size-related standards similar to the one available for batteries. There is no standard fuel cell product that can be used as a power pack for all brands of the same electronic device. Currently micro fuel cells are quite expensive due to the use of noble metal catalyst and tiny pumps, fans, valves etc. for the reactant supply, recirculation, thermal, water management and product handling. Air traffic regulation could prohibit use and transportation devices fitted with micro fuel cells due to the flammable nature of most of the fuels used in these devices. The peak power rating of many of the micro fuel cells are inferior to that of batteries resulting in their inability to meet some of the functional requirement of microelectronic devices. 

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