摘要
研究了添加剂P2 O5 对锂离子蓄电池材料LiNiO2 的影响。添加P2 O5 的目的是提高LiNiO2 的放电平台和充放电稳定性 ,增加循环寿命 ,提高充放电能量。在n(LiOH) /n(β Ni(OH) 2 ) (摩尔比 )为 1 .1∶1 .0的混合材料中加入P2 O5 ,保持n(P) /n(Ni)为 0 .0 1、0 .0 2、0 .0 3、0 .0 4和 0 .0 5。分析测定了样品的充放电特性曲线和循环伏安曲线 ,并作了XRD结构分析。结果表明 ,当n(P) /n(Ni) =0 .0 2时 ,LiNiO2 的放电电压有提高 ,P2 O5 使LiNiO2 在充放电过程中的晶型转变过程发生改变 ,使六方晶系向单斜晶系转变的趋势变小。添加P2 O5 没有影响锂离子的嵌入和脱嵌机制。当n(P)∶n(Ni) =0 .0 3时 ,LiNiO2 的XRD图上的 (0 0 3)峰强度变小。 (0 1 8)和 (0 1 9)峰也有改变 ,这证明了LiNiO2 的层状结构发生变化 ,并导致LiNiO2 的电化学性能降低。P2 O5 合适的添加量是n(P) /n(Ni)为 0 .0
The effect of additive P 2O 5 on LiNiO 2 material used in lithium ion battery was studied. The aim of adding P 2O 5 was to improve the discharge plateau and the charge/discharge stability of LiNiO 2 as well as to increase its cycle life and charge/discharge energy. P 2O 5 was added into the mixed powder of LiOH and β Ni(OH) 2 with their mole ratio n(LiOH)/n(β Ni(OH) 2)=1.1∶1.0, and n(P)/n(Ni) were kept 0.01, 0.02, 0.03, 0.04 and 0.05 respectively. The charge/discharge curves and cyclic voltammogram of the sample were determined and the XRD pattern of the sample was tested. The results show that the discharge voltage of LiNiO 2 is increased when n(P)/n(Ni)=0.02, and the process of crystal form transformation of LiNiO 2 was changed as well as its transforming tendency from hexagonal system to monoclinal system was decreased by adding P 2O 5 in. P 2O 5 does not affect the intercalation and extraction of Li +. However, when n(P)/n(Ni)=0 03, the strength of (003) peak in XRD pattern of LiNiO 2 damps and those of the (018) peak and (010) peak also change. It proves that the lamellar structure of LiNiO 2 is changed so that the electrochemical property of LiNiO 2 is decreased. The suitable amount of additive P 2O 5 is n(P)/n(Ni)=0.02.
出处
《电源技术》
CAS
CSCD
北大核心
2000年第3期141-143,共3页
Chinese Journal of Power Sources
基金
辽宁省科委自然科学基金项目 !( 9810 30 0 70 2 )
