Abstract: Disclosed is a method for preparing a high performance, negative electrode for Ni/metal hydride cells. A Zr-based hydrogen storage alloy, a binder comprising a mixture of polytetrafluoroethylene and 50th and a thickening agent (hydroxypropylmethyl cellulose), and a current collector comprising carbon black and copper are slurried and molded into a paste-type electrode. In a closed type cell, the copper repetitively undergoes melting and deposition on the electrode during charging and discharging cycles, allowing the electrode to show a similar change in surface morphology and electrochemical properties to that of a conventionally electroless plated electrode.

Abstract: Disclosed is a method for modifying a surface of a hydrogen storage alloy for an Ni/MH secondary battery using flake type metal comprising the steps of ball-milling metal powder to produce flake type metal powder; and ball-milling the flake metal powder together with hydrogen storage alloy powder to obtain mixture powder. The method according to the present invention provides the hydrogen storage alloy capable of increasing discharge capacity of an electrode and lengthening electrode life duration for the Ni/MH secondary battery.

Abstract: Disclosed is a carbonaceous material for anodes of lithium ion rechargeable batteries. The carbonaceous material consists of soot particles which are prepared from liquified propane gas through thermal decomposition. The soot particles are of disordered or amorphous carbon with very small crystallite sizes (La, Lc≦30 Å), containing a large quantity of unorganized carbon. When being used as an active material for an anode of a lithium ion secondary cell, the soot shows far greater reversible capacity than do conventional graphite carbonaceous materials.

Abstract: There are disclosed Mm/Ni type hydrogen storage alloys for Ni/MH secondary cells. The alloys which allow the cells to be of high performance and high capacity can be prepared at lower costs than the production costs of conventional Co-rich hydrogen storage alloys, by reducing the amount of the Co element. The Co element is partially or wholly replaced by by Cr, Cu, Fe, Zn and/or Zi, which are each known to be of stronger affinity for hydrogen than is Co and to have such a strong oxidation tendency in electrolytes as to form a highly dense oxide. The novel alloys have discharge capacities and electrode life span as good as those of the conventional Co-rich hydrogen storage alloys but have advantages over the Co-rich alloys, including performance-to-cost.

Abstract: A method for producing an electrode of Ni/metal hydride alloy secondary cells. The electrode may be produced by mixing an active material with approximately 10-50 wt % of Cu powders, which can serve as a binder as well as a current collector, and cold-pressing the mixture at a pressure of 10 ton/cm. As the Cu-compacted electrode continues to experience the cycle of charge and discharge, the desolution-deposition of Cu is gradually produced. This desolution-deposition of Cu allows Cu to be deposited on the surface of the electrode comprising the hydrogen storage alloy, so that the electrode can be similar to a conventional Cu-electroless plated electrode in surface morphology. Consequently, the method of the invention can be an alternative for conventional electroless plating, which significantly improves the general functions of hydrogen storage alloy electrode, including low temperature dischargeability and high rate capability, without producing pollution of the environment.

Abstract: The present invention provides a hydrogen-absorbing alloy system of ultra high capacity for electrode of secondary battery. In accordance with the present invention, the hydrogen-absorbing Ti alloy system is represented as a following general formula:Ti.sub.A Zr.sub.B V.sub.C Mn.sub.D Ni.sub.E M.sub.Fwherein, M represents at least one metal which is selected from the group consisting of Cr, Co, Fe, Cu, Al, Si, Hf, Nb, Mo and R.E., where R.E. represents at least one metal which is selected from the group of rare-earth elements consisting of La, Ce, Pr, Nd and Sm; and, A, B, C, D, E and F have atomic ratios ranging 0.2.ltoreq.A.ltoreq.0.35, 0.03.ltoreq.B.ltoreq.0.15, 0.15.ltoreq.C.ltoreq.0.4, 0.8.ltoreq.D.ltoreq.0.2, 0.13.ltoreq.E.ltoreq.0.35 and 0.ltoreq.F.ltoreq.0.1, respectively, with the proviso that A+B+C+D+E+F=1 and A+B.ltoreq.0.45.

Abstract: The present invention relates to a material for hydrogen-storage constituted by Ti-Mn alloy system which has a high hydrogen-storage capacity, plateau hydrogen dissociation equilibrium pressure, hypostoichiometric composition and crystal structure of C14. Ti-Mn alloy system for hydrogen-storage of the invention which has a C14 crystal structure, is represented as: Ti.sub.u Zr.sub.v Mn.sub.w Cr.sub.x V.sub.y X.sub.z, wherein, X is at least one of element selected from the group consisting of Fe, Al and Ni; u, v, w, x, y and z are mole numbers of each components; 0.7<u<1.0; 0<v<0.3; 1.0.ltoreq.w.ltoreq.1.3; 0.1.ltoreq.x.ltoreq.0.4; 0<y<0.3; 0.ltoreq.z.ltoreq.0.2; 0.7<u+v<1.0; 1.4.ltoreq.w+x.ltoreq.1.7; and, 1.3.ltoreq.w+x+y+z<2.0.

Abstract: The present invention provides a method of activation treatment of a Ni/MH secondary battery which comprises a step of immersing an electrode or battery in a solution or electrolyte and charging/discharging concurrently. In accordance with the activation treatment of a Ni/MH secondary battery by hot-charging method of the invention, the time required for activation treatment is remarkably saved and the activation process is carried out in a highly efficient manner, compared to the conventional methods of activation treatment.

Abstract: The present invention relates to a process for preparing an electrode for secondary battery employing hydrogen-storage alloy systems, more specifically, to a process for preparing an anode material for secondary battery which can be charged/discharged in an electrolyte and has a high discharge efficiency and energy density per unit weight, by sintering a mixture of hydrogen-storage alloy systems. An electrode for secondary battery of the present invention is prepared by the process which comprises the steps of: (i) mixing a hydrogen-storage alloy powder free of Ni with a hydrogen-storage alloy powder containing Ni over 30 atomic %; (ii) cold-pressing the mixed powder at a pressure of 5 to 15 ton/cm.sup.2 ; (iii) sintering the cold-pressed mixture in a quartz tube at 900.degree. C. for 5 to 15 min under a vacuum condition of 10.sup.-2 to 10.sup.-3 torr; and, (iv) quenching the sintered material.