Study On High Performance Battery Separator Of MH-Ni Battery

As the increasing usage of the battery in daily life, people pay more attention on high capability battery. And so, the technology of battery producing has been advanced. The battery separator is located between the positive plates and negative plates so as to provide a separation between the electrodes of opposite charge and an electrolyte reservoir. So the battery separator is one of the most important factors that influence battery capability. Constituted chemical fibers, the battery separator generally produced by wet-laid process. The production is accomplished on traditional paper machine, and the battery separator is called a kind of special paper or wet-laid nonwoven. Compared with traditional paper manufacturing process, wet-laid process production of chemical fibers has many special manufacture methods. High required of hydrophilic character, the battery separator made from chemical fibers need to be treated to hydrophilic. The production method of the battery separator was studied in this paper.The consistence of the stock of chemical fibers should be less than that of the plant fibers, and the dispersion and the deformer should be employed to the stock. We found that it better to add the additives into the water before the addition of the fibers. It should decrease the times of the transfer of the stock and ensure the lubricity of the stock piping.The hydrogen bonds, which exist in plant fibers paper, don't exist in the paper that made by chemical fibers. There is only interweavement of chemical fibers, so that, the tensile strength of the nonwoven fabric is very poor. The paper adopt the hot-melt fibers(ES fibers) which is sheath-core structure, at a certain pressure and temperature, the sheath of the fiber was melted and the fibers fused together, so that, the tensile strength of the paper is advanced.The paper is made by the dividable composite fibers(DCF) and ES fibers, the proportioning of the two kinds of fibers effects the absorption and tensile strength of the paper distinctly. We elevae the allround performance of the paper by changing the structure of the paper, the experiment proved that the three-layers structure paper is functional. The paper, the face-layers of which are made by ES fibers and the core-layer is made by 40% ES fibers and 60% DCF, has a better performance, and it fits for the production of the battery. But the alkali stripping ratio of the paper is a little high.It is better producing the high performance battery separator by 100% ES fibers. Being hydrophobic, the ES fibers paper should be treated to hydrophilic.The usual hydrophilic treating methods are strong oxidizer treatment, strong acid-potassium dichromate treatment and plasma treatment. It is proved that the three hydrophilic treating methods are all efficiency. Every method has its own merit, and the one fitting the circumstances should be selected.