CHEM 112 Lecture Notes - Lecture 1: Lithium Polymer Battery, Lithium-Ion Battery, Lead Dioxide
Document Summary
Batteries and fuel cells, electrolysis: primary cells (or batteries). Cell reaction is not reversible: secondary cells. Cell reaction can be reversed by passing electricity through the cell (charging): flow batteries and fuel cells. Materials pass through the battery which converts chemical energy to electric energy. The leclanch dry cell is the most common type of voltaic cell, invented by georges leclanch in the 1860"s. It is called a dry cell because there is no free liquid present. It is cheap to produce, but as a primary cell, cannot be recharged. Acid-base reaction: nh4 + (aq) + oh- (aq) nh3 (g) + h2o(l) Precipitation reaction: nh3 (g) + zn2+(aq) + 2 cl- (aq) [zn(nh3 )2 ]cl2 (s) The nh3 (g) must be removed by complexing it to zn2+ or it will adhere to the cathode, disrupting the current. Reduction: 2 mno2 (s) + h2o(l) + 2 e - mn2o3 (s) + 2 oh- (aq)
