题目

阅读理解 I went to the Tsavo National Park in northern Kenya for a film. We set off early for a distant water hole. A huge elephant covered with dry mud, drank calmly and deeply. He might have traveled 50 km to reach the water. He wasn't going to hurry now. We thought he'd drink a while and rest in the shade, and then drink again. What actually happened was that he drank deeply and stepped away. Then he suddenly fell down. Within minutes he was dead. We called animal doctor Jeremiah Poghon immediately. He removed the head of a poisonous arrow (箭) from the elephant's body, and let out ove 锂离子电池正极材料是含锂的二氧化钴(LiCoO2)，充电时LiCoO2中Li被氧化，Li+迁移并以原子形式嵌入电池负极材料碳(C6)中，以LiC6表示．电池反应为LiCoO2＋C6CoO2＋LiC6，下列说法正确的是 [　　] A． 充电时，电池的阳极反应为LiC6－e－Li＋C6 B． 放电时，电池的正极反应为CoO2＋Li+＋e－LiCoO2 C． 用含锂离子的水溶液做该锂离子电池的电解质 D． 该锂离子电池的比能量(单位质量释放的能量)低