Research On Anode Material Of Nickel-Metal Hydride Ultrabattery

In this thesis, a kind of MH-Ni ultrabatteriy was designed and prepared in accordance with the demand for high capacity and high power batteries in the market. The anode materials of MH-Ni ultrabatteries were prepared through adding active carbon to hydrogen storage alloys by mixing and fencing processes, respectively. MH-Ni ultrabatteries were using above mixed materials as anode materials according to industrial production methods prepared in order to improve dynamic performance of MH-Ni batteries.The electrochemical properties including the maximum stable discharge capacity, cycle life, charge retention ratio, high rate charge-discharge abilities and low-temperature discharge capacity were studied. The results showed that the electrochemical properties of MH-Ni ultrabattery prepared by fencing process were not good, while the electrochemical properties of MH-Ni ultrabattery prepared by mixing process were very well. The high rate charge-discharge abilities improved obviously. The discharge efficiency was73%greater than68.6%of MH-Ni batteries at3C rate and the charge voltage was1.6V smaller than1.8V of MH-Ni batteries at3C rate. After350cycles, the discharge capacity could still reach95.6%of the maximum stable discharge capacity, but the charge retention ratio declined. The mixing process was more suitable to prepare MH-Ni ultrabatteries than the fencing process by contrast experiments.