| Co(OH)2 as additive of secondary batteries has been attached great importance. Several investigations were focused on the synthesis and the electrochemical properties of Co(OH)2. However, the traditional preparation methods needs several steps, consuming lots of energy, and even the products is difficult to filtrate and easy to be oxidized. Therefore,β–Co(OH)2 was synthesized by solid-state reaction and electrochemical properties were tested in this paper. X-ray diffraction (XRD), Field-emission scanning electron microscope (FE-SEM) and thermal gravity (TG) were employed to determine the microstructure, morphology and weight losing, respectively. Moreover, the effect of additives on electrochemical properties ofβ–Co(OH)2 electrode was investigated. The possibility of theβ–Co(OH)2 as the candidate materials for negative electrodes of batteries was discussed.The XRD showed that the as-synthesized sample wasβ–Co(OH)2 with hexagonal structure. FE-SEM indicated that the size of theβ–Co(OH)2 powder was less than 500 nm. Theβ–Co(OH)2 electrode can be activated within 2 cycles and reached the maximum discharge capacity of 466 mAh/g. Theβ–Co(OH)2 exhibited high rate chargeability. The ratio of HRC1500 vs. HRC60 was 83.5%. Theβ–Co(OH)2 electrode was sensitived to temperature. From 293 to 333 K, the discharge capacity increases, while the discharge platform descends. The drawbacks ofβ–Co(OH)2 used as electrode materials were lower discharge platform and undulation of the discharge capacity during charge-discharge cycling.The additives improved the high rate dischargeability ofβ–Co(OH)2 electrode. The improvement order is graphite>activated charcoal>La2O3>copper powder. The discharge platform is 1156 mV (with graphite) and 1150 mV (with La2O3), respectively, while that of the blank electrode is 1138 mV. The cycle stability ofβ–Co(OH)2 with an additive has also been improved.
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