Shoji Tsushima

Design of the Experimental Procedures for Analysis of Thermal and Electrical Properties of a Prismatic LiFeYPO4 Battery in a Modified Electric Car

As being the most important part in the energy supply system, the battery must be carefully monitored in order to optimize the performance and to prolong its life. The most affected parameter to the battery is the operating temperature as the higher operating temperature increase the performance but shorten the life and with lower operating temperature can ensure longer life but reduce the performance. With this, the battery thermal management system is created in order to keep the operating temperature at the suitable range. In order to achieve this, thermal behaviour in loaded condition must be analysed beforehand. A series of experimental procedures is designed for the selected lithium iron phosphate battery to determine the thermal properties such as heat capacity, heat generation, and cell temperature according to the electrical load applied. Derived thermal model of lithium ion battery was utilized for this purpose as it shows the relationship between the thermal, electrical properties and other parameters such as voltage, current and cell temperature. When the battery is applied with electrical load, the data of voltage, current, and surface cell temperature can be used to determine the thermal properties and at the same time, electrical properties such as open circuit voltage, state of charge and internal resistance are also obtained for the performance evaluation.

Study on two-phase flows in porous rocks in CO2 geological storage

Though CO2 leakage from a geological storage site through wells and rifts represents a major concern, it is difficult to monitor the CO2 leakage. In this paper we have experimentally investigated the proton relaxation time (T1) of carbonate-water filled in a porous media at high pressure with an NMR system to see the dependence of T1 on the concentration of CO2. From the results, it has been observed that the higher the CO2 concentration is, the shorter the T1 of the carbonate-water in the porous media becomes. Therefore this information is very useful to apply NMR logging to monitor the CO2 leakage.

Experimental Studies on Liquid CO2 Injection with Hydrate Film and Highly Turbulent Flows Behind the Releasing Pipe

CO 2 ocean sequestration is considered to be an effective global warming countermeasure. One of CO 2 ocean sequestration methods is releasing liquid CO 2 droplets in intermediate depth of ocean, which leads to direct dissolution of CO 2 in seawater. To discuss implementation of CO 2 ocean sequestration, it is necessary to evaluate dissolution process of CO 2 in seawater. Released liquid CO 2 droplets from a towed pipe are dispersed into the sea vertically due to buoyancy effect and horizontally due to turbulent mixing behind the pipe. In terms of vertical dispersion of CO 2 , initial droplet size is of importance because velocity of droplet rising due to buoyancy and surface area of dissolve droplet are dominated by droplet size, while in horizontal dispersion, turbulent mixing behind the pipe have a key role. This chapter presents two different types of experiments related to releasing CO 2 into the ocean by a towed pipe: (1) investigation of injection behaviors of liquid CO 2 with hydrate, varying injection velocity, and surrounding temperature, and (2) visualization of highly turbulent flow over the critical Reynolds number around a circular cylinder simulating the towed pipe.