Pulse Quick Charger of Electric Vehicle

In order to improve the charging efficiency of lead acid battery, shorten the charging time and avoid the battery polarization, a new charging method was put forward. Based on the analyzed results of charging characteristic of lead acid battery, a pulse quick charger is designed to adjust the charging current pulse’s amplitude and pulse width automatically stage by stage according to the measured battery voltage and feedback current. Compared with other kinds of quick chargers, it has such characteristics as shorter charging time, higher charging efficiency and lower temperature increasing during the charging process. As a result, the battery polarization is reduced efficiently.

Development of Management Systems for Electric Vehicle Battery Series

A kind of management system for electric vehicle (EV) battery series was developed. The system can predict residual capacity for EV battery series and mileages. The system can determine if it is necessary for the battery series to be charged. The system can determine which battery is necessary to be updated for the reason of damage or aging. The system can display the total voltage of battery series, extreme voltage and temperature of every battery in the series. The system can display the accumulative discharge for every battery in the series. The system can alarm when both total or extreme voltage is at low level, or temperature of a battery in the series is at high level. The system provided with a microprocessor as key part can collect and record signal of charging and discharging current, total voltage, extreme voltage and temperature for every battery. The mathematical model of residual capacity for EV lead acid batteries was discussed in details. The system operates well in the laboratory and meets the requirement.

Parametric optimization of power system for a micro-CCHP system

The universal mathematical model of an engine is established,and an economical zone,in which an engine mainly provides medium output load at medium speed,is presented.Based on the experimental data and the universal model of such an engine above,a mathematical model of a refitted engine is provided.The boundary of the corresponding economical zone is further demarcated,and the optimal operating curve and the operating point of the engine are analyzed.Then,the energy transforming models of the power system are established in the mode of cooling,heating and power（MCHP）,the mode of heating and power（MHP）and the mode of electricity powering（MEP）.The parameter matching of the power system is optimized according to the transmission ratios of the gear box in the power distribution system.The results show that,in the MCHP,the speed transmission ratio of the engine to the gear box（ies）and the speed transmission ratio of the motor to the gear box（ims）are defined as 2.9 and 1,respectively;in the MHP,when the demand load of the power system is less than the low critical load of the economical zone,the speed transmission ratio of the motor to the engine（ime）is equal to 1,and when the demand load of the power system exceeds the low critical load of the economical zone,ime equals 0.85;in the MEP,the optimal value of ims is defined as 2.5.

A new state of charge determination method for battery management system

State of Charge (SOC) determination is an increasingly important issue in battery technology. In addition to the immediate display of the remaining battery capacity to the user, precise knowledge of SOC exerts additional control over the charging/discharging process which in turn reduces the risk of over-voltage and gassing, which degrade the chemical composition of the electrolyte and plates. This paper describes a new approach to SOC determination for the lead-acid battery management system by combining Ah-balance with an EMF estimation algorithm, which predicts the battery’s EMF value while it is under load. The EMF estimation algorithm is based on an equivalent-circuit representation of the battery, with the parameters determined from a pulse test performed on the battery and a curve-fitting algorithm by means of least-square regression. The whole battery cycle is classified into seven states where the SOC is estimated with the Ah-balance method and the proposed EMF based algorithm. Laboratory tests and results are described in detail in the paper.

Design and analysis of an electric-locomotive turning system for coal mines

We describe a system for turning the accumulator electric locomotives used in coal mines. This improves transport efficiency and decreases mine construction and production costs. The operating requirements, principles, working features and transmission system are discussed. This system has a simple structure and can be manufactured, transported and assembled easily. It, therefore, can handle accumulator locomotives of middle and small size.

Addition of Ce as additive to Pb-Ca-Sn-Al grid alloy for lead acid battery

The study on three Pb Ca Sn Al alloys with 0.08%, 0.4% and 1.0% of Ce indicates that the addition of Ce results in an obvious increase in the tensile strength and hardness of the alloys, an increase in the overpotentials of hydrogen and oxygen evolution and the corrosion resistance as well. The study on the corrosion film formed on the alloys by cyclic voltammetry shows that the addition of Ce slows down the formation of corrosion film. It is therefore concluded from the experimental results that the addition of Ce can increase the tensile strength and HB of Pb Ca alloy and the tensile strength and HB of the alloy increase with the increase of Ce; the addition of Ce also increases the hydrogen and oxygen evolution overpotentials of Pb Ca alloy, and when the content of Ce is 1.0%, the alloy has the highest hydrogen and oxygen evolution overpoteatials; the addition of Ce improves the anticorrosion capability of the alloy, and when the content Ce is 1.0%, the alloy has the best anticorrosion capability; and the addition of Ce also slows down the formation of corrosion film.

Effect of Properties of Carbon Materials on Performance of VRLA Batteries

In the present study, the relationship between properties of different carbon materials and their impact on performance of VRLA （valve regulated lead acid） battery was studied. The material properties undertaken for the study are： surface area, conductivity and water absorption of the carbon. The electrode morphology revealed the uniform distribution of active material when high surface area carbon was added to NAM （negative active material）. The porosity of the plate also exhibited changes with respect to type of carbon materials added. The study further revealed that, the addition of high surface area carbon （-1,400 m^2/g） improves the charge acceptance of the battery with higher loading. Further improvement in charge acceptance was observed with addition of graphite to higher surface area carbon. Nevertheless, the float current of the battery got affected due to graphite loading and found there was no impact on shelf life of the battery in all the cases. The study demonstrates the need for customized ＂carbon formulation＂ to obtain the maximum performance out of the battery.

Effect of lead foam grid on performance of lead-acid battery

In order to increase the specific energy and specific power of a lead-acid battery, lead foam grid was prepared by electrodepositing Pb-Sn alloy on a copper foam substrate and used as negative current collector for a lead acid battery whose capacity was limited by the negative plate. Comparing the effect of the cast grid, under the same conditions, the mass of lead foam grid decreases by 35%, and the area of lead foam contacted with active material increases by about 20 times. Under 2 h rate discharge condition, with a high current （3 0 I2） e and low-temperature （-10 ℃, I2） discharge system, the lead foam grid markedly boosts the discharge performance of lead acid battery. It increases not only the negative electrode mass specific capacity by 27%,37% and 29%,but also the utilization efficiency of the negative active material by 5%. Compared with the negative electrode of cast grid, XRD and SEM results show that after 20 cycles at the state of charge, the sponge lead in the negative lead foam electrode has smaller crystals and less PbSO4 on its surface. Meanwhile, at the state of full discharge, the PbSO4 crystals are smaller and occur less on the surface of lead foam electrode. This indicates its active material reacts more uniformly.

A study on equivalent circuit model of lead-acid battery for electric vehicles

A 100Ah@42V lead-acid battery package for electric vehicles are used for study. 1he hybrid pulse test is applied to the battery package to acquire enough data, by which the partnership for a new generation of vehicles （PNGV） equivalent circuit model parameters are identified by the least square method. Then, the PNGV model is verified under two conditions, i.e., the composite pulse excitation and the constant-current respectively. The corresponding maximum relative errors of output voltage are less than 3 % and 3.5 %. Results show that the present PNGV equivalent circuit model and verification method is effective, which can satisfy requirement of simulation of power system of electric vehicles.

A Design of the Automatic Power-off after the Storage Battery of Electric Bicycle Is Fully Charged

As the service life of the electric bicycle＇ s storage battery is shortened due to the long-term floating charge, an automatic power- off circuit for the storage battery of electric bicycle is designed, and also the composition and design of the circuit are specifically expounded. After a test, the circuit can achieve a desired effect. Therefore, it can prolong the service life of the electric bicycle＇ s storage battery and save electric energy in the actual applications.

Electrochemical performance of nano-scale β-Ni(OH)_2 prepared at different transformations of pH value

The influence of transforming pH values on the electrochemical performance of nano-scale Ni （OH）2 was analyzed. The measurement results of XRD indicate that the nano-scale Ni （OH） 2 prepared at different transformations of pH value is β （ Ⅱ ）-phase with different crystal lattice parameters. Cyclic voltammograms （CV） and electrochemical impedance spectroscopy（EIS） measurement results show that transformations of pH value affect the proton diffusion coefficient （D） and charge-transfer resistance （Re,） of the material. The simulation of.cell experiment shows that the sample prepared at a pH of 10. 1 exhibits the maximum specific capacity （327.8 mAh/g） and higher discharge platform, the discharge performance of electrodes depends on both D and Rct, so the kinetics characteristics that electrodes reaction is controlled by both mass-transfer step and charge- transfer step are put forward.

多功能自来水充电发电节能系统

多功能自来水充电发电节能系统由一台或多台小型水流发电机组成。通过电路设计,在有水流通过的时候,水流发电机进行发电并积蓄在模块化蓄电池中;当水流停止的时候,蓄电电池可拆卸用做移动电源或直接将电能供给到LED灯。多功能自来水充电发电节能系统可以应用到家庭的水龙头红外线感应装置或用来随身携带应急充电;移动电源上的LED灯可以用作洗手间照明或手电筒。也可直接将电量供给于景区、商场、小区和学校等用水量较大的单位,让节能应用在实际生活中,达到节能减排并方便人们生活的效果。