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Batteries have been widely used in the residential electric systems. This paper firstly analyzes the characteristics and feasibility of using the battery to participate in Demand Response (DR) programs. Secondly, the load characteristics in the two different kinds of battery systems are studied, including the power battery of electric bicycles and the battery which are used as the standby power for communication systems and computer systems. Thirdly, this paper studies the DR implementation method of reducing peak and filling valley and related impact on power grid load.

The estimate of the remaining capacity of power battery is one of the most important function of battery management system. Using traditional methods is difficult to estamate the remaining capacity, this paper put forward a new method which is based on the battery model and extended Kalman filter.Then carries on the concrete analysis and discussion.

Green performance assessment of power battery is a whole life cycle process, which integrates Environment (E), Resource (R), Technology (T) and Cost (C) objectives considered as evaluation of multi-objective and multi-stage. According to definition of Green Product, the assessment model of multi-objective and multi-stage for power battery was built. The green utility function is proposed, by which the evaluation data of indices are changed uniformly into range of (0, 1) according to the assessment standard initialized as 0.5. The synthesis calculation method is given, which remains all the messages in the assessment. Finally, the green performance comparison between lithium-ion battery and nickel metal hydride battery proves the assessment method and process.

In the Ni-MH power battery electrodes manufacturing, the quality of the electrode material admixture will affect electrode and the whole function of batteries directly. However, the electrode material admixture process is very complex. It is very difficult to build up a model of precision to carry on control to the system. The traditional electrode material admixture control of the process, mainly according to develop the personnel on trial and the spot experience to complete, That method basically can not reach the good control appearance. The Fuzzy control can resolve the problem of this complication nicely.

The shortage of energy prompted the Li-ion power battery to become the new alternative energy. As the main body of the Li-ion power battery, the electrode has a great influence on safety, performance, cycle life and capacity of the battery. Thus, it is necessary to inspect surface defects of the electrode precisely. Then, a new inspection method is proposed in this paper. In the method, the machine vision based on smart camera and combined with LabVIEW which is the graphical and virtual programming software is applied to inspect defects of the electrode. This combination of hardware and software is helpful to improve the efficiency of the electrode inspection.

Li-ion power battery is one of the key technology for electric vehicle and the most important technology for the producing the Li-ion power battery is coating. At present, the ways of Li-ion power battery coating mainly are the roller coating and the slot extrusion coating. As the roller coating technology is the proven technique and the equipment is simpler, it is a better choice. The key technology of the roller coating is ensuring thickness uniformity and accuracy of the battery electrode. According to the production sample data analysis of the roller coating device, the coating machine we developed successfully achieved the required technical indicators.

With the deterioration of the environment and energy crisis is becoming more and more serious, the development of low carbon industry has risen to national strategies. In the energy utilization and environmental effect, electric vehicle to the fuel vehicle has the advantages of energy saving and emission reduction prominent; the whole life cycle analysis, the electric vehicle complete life cycle into electric energy transmission cycle and vehicle life cycle of two parts; electric vehicle power battery as storage unit, strengthen the relationship between electric vehicle, new energy and smart grid among the three, promotes the development and application of clean energy, speed up the construction of smart grid, realize the real energy-saving and emission-reduction.

The green environmental Li-ion power battery becomes the research heat spot of new energy technique and gets people's more and more attentions. This article overviews the process of coating technique of the Li-ion power battery, and the drying technique of Li-ion power battery electrode has a great influence on the Li-ion power battery performance. After analyzing the principle and merits and demerits of various dry methods of Li-ion power battery electrode, the project decides to apply hot-wind of circulating and shock drying method to dry Li-ion power battery electrode. The method has already successfully applied to practice production and has obtained a good economic efficiency for enterprise.

As the only power source of electric vehicles (EVs), power battery pack is also the main fault source in EVs. The faults of power battery affect its performence and life, and even endanger vehicle security in extremly situation. Early fault diagnosis of power batteries can reduce losses, minimize maintenance, guarantee vehicle performence, security and realibility. In this study, the faults of power batteries are summarized, four fault diagnosis methods are concluded and analyzed, and the applicability of each method is compared and discussed. The principle of choosing the diagnosis method is that choosing according to the diagnostic condition.

In order to know how inconsistency of power battery pack evolves during work, capacity range of cells was studies. The characteristic of operating circuit of power battery pack both in parallel connecting and in serial connecting was analyzed. Then, ratio models with parameters such as charging/discharging rate and depth of discharging of each cell in pack were studied. Remaining capacity of a cell was calculated according to the capacity degradation model. Evolution model of capacity range of cells in pack was established. Based on that of parallel or serial connecting, evolution models of capacity and capacity range in hybrid connecting were established too. Models established here would be helpful to determine cycle life of power battery pack.

To resolve the problems that the initial state of charge (SOC) and the available capacity of batteries are difficult to estimate when using the Ah counting method, in this paper An improved SOC estimation method was proposed that combined with the open circuit voltage (OCV) method and Ah counting method based on the analysis and consideration of the battery available capacity variation caused by charge and discharge current, environment temperature and battery state of health (SOH). The precision of the proposed method was validated by using Federal Urban Driving Schedule (FUDS) test of a Lithium iron phosphate (LiFePO4) power battery. The SOC estimate error using the proposed method relative to a discharge test was better than the Ah counting method.

Power battery in the HEV normally has a high capacity. Therefore during the start-up procedure of HEV motor, pre-charge phase is essential in order to reduce the impact of high current. In this paper, we build a HEV motor pre-charge model then deploy it on cRIO embedded control system to simulate the whole process with high real time. Finally the paper tests some typical fault conditions which demonstrate great benefits.

The thesis studied the monomer power battery, in order to overcome the difficulty in state of charge(SOC) online testing, the thesis put forward a new method to do SOC online estimation. By studying the rebound voltage caused by lead-acid battery when it is offline, with the consideration on elements as discharge rate, depth of discharge, temperature environment and so on, the thesis build a function relation between the rebound voltage and the SOC; with the adoption of 89S51 micro-controller in real-time measurement and calculation, we successfully estimated the SOC of intelligent traction–battery online.

With the large-scale use of power battery pack, its security issues are attracting more attention, especially insulation faults. Traditional insulation monitoring methods can only detect insulation faults appeared at the most positive and negative ends of the battery pack, which cannot meet the requirements of monitoring the insulation state of an entire battery pack system. This paper analyzed the multi-point grounding insulation model of power battery pack, and obtained an equivalent model. A method of detecting the insulation resistance and locating the insulation fault was given, based on the equivalent model. The results of the simulation on Multisim 10.0 and the experiment test proved the correctness of the simplifying process of the insulation model and the insulation monitoring method.

With the continuous development of pure electric vehicles, lithium-ion battery is getting more attention. The SOH is characterized by the capacity of battery charging and discharging, so to meet the national regulations, it is necessary to detect it. This article focuses on estimating the current SOH of the battery based on voltage characterization when charging, and realizes real-time detection of health status in remote monitoring system.

Power battery thermal management system (BTMS) is very important for the safe operation of electric vehicles (EVs). The cooling effect of air cooling, phase change material(PCM)cooling and liquid cooling applyed to BTMS are compared. The experiment results show that, in comparison with air cooling, PCM cooling and liquid cooling methods can reduce the battery temperature rise effectively; in comparison with PCM cooling, liquid cooling has a better effect in the aspect of controlling the battery temperature rise.

It is very important to monitor and estimate thermal stability of the power battery because that the thermal runaway will happen at some high temperature. Therefore, this study was focused on thermal stability estimation of the power battery thermal stability. The thermal stability estimation model consists of collect module, judge module, cusp catastrophe estimation module and control module. The important module is cusp catastrophe estimation module which was established based on cusp catastrophe theory. The experimental results show that thermal stability estimation model of the power battery works well. Therefore, thermal stability estimation model of the power battery is helpful to monitor and estimate the safety and reliability of power battery on line.

The short driving range and long charging time are two big problems for electric vehicles. A concept of battery pack automatic replacement is put forward in this paper to solve these problems, and a deep research on the key techniques is contained. This paper introduced the way of positioning and locking in replacement process, including the concrete structure of both replacing equipment and battery pack. For reliability problems of the connectors, two schemes are designed. Elastic jacks and coil are adopted to guarantee the reliability and automatically centering. On this basis, battery fast replacing system is designed, which controlled by PLC, driven by electro-hydraulic servo. This was proved to be a big success in practice.

Carbon-doped LiFePO4/C cathode materials for lithium power batteries were prepared by liquid-state precipitation reaction. Their properties were studied by using XRD, SEM, elemental analysis, FTIR and A.C. impedance tests. The results showed that the samples with olivine structure and 3.4V discharge platform. The tapped density of LiFePO4/C sample could reach 1.42g/cm3, and it had an initiate capacity of 144.6mAh/g at 0.2C, and 93.2% of which remained after 20 cycles. The first discharge specific capacity is 133.5mAh/g at 10C and the capacity decreased 8.76% after 20 cycles.

To have a fundamental understanding on the principle of carbon aerogels when it is used as electrode materials in power battery, the effects of density and structural properties on the electrical conductivity of carbon aerogels was investigated in this paper. Carbon aerogels with different density were prepared via adjusting the chemical conditions of the primary solution. The morphology of carbon aerogels were observed by field emission scanning electron microscopy (FE-SEM). Experimental results show that the electrical conductivity of carbon aerogels is ranged from 10-6 Ω/cm to 10 Ω/cm, and that not only the density but also the carbon particle size and porosity of carbon aerogels effect the transport property greatly. With the increasing of the density the electrical conductivity of carbon aerogels increases. This indicates that larger particle size and lower porosity of the nano-structure lead to higher conductivity.