Historical clue formulations

• Battery type — 2024-05-15
• Common kind of battery — 2022-08-26
• Battery type — 2021-12-25
• Kind of battery — 2018-11-11
• Hybrid kind of battery — 2014-01-27
• Certain dry cell, briefly — 2008-10-10
• Battery type — 2006-03-15
• Certain battery — 2001-12-21
• Kind of battery — 2000-11-23