US 12,463,214 B2
Negative electrode active material and battery
Haruyuki Nakanishi, Nagoya (JP); and Haruo Sawa, Kochi (JP)
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed by TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed on Nov. 18, 2021, as Appl. No. 17/530,016.
Claims priority of application No. 2020-203394 (JP), filed on Dec. 8, 2020.
Prior Publication US 2022/0181623 A1, Jun. 9, 2022
Int. Cl. H01M 4/58 (2010.01); H01M 10/30 (2006.01); H01M 4/02 (2006.01)
CPC H01M 4/58 (2013.01) [H01M 10/30 (2013.01); H01M 2004/027 (2013.01)] 9 Claims
 
1. A negative electrode active material incorporated into a battery, the negative electrode active material comprising:
an iron compound, the iron compound containing a salt of a polyoxygen anion with iron, wherein
the polyoxygen anion has a first atom and an oxygen atom, the first atom is at least one type of atom selected from atoms belonging to Group 4, Group 5, Group 6, Group 13, and Group 14 in the periodic table of elements, and
a molar ratio of the oxygen atom to the first atom in the polyoxygen anion is more than 1,
the polyoxygen anion is a carbonate ion,
the negative electrode active material is configured to charge by the reaction expressed in Formula (1), and
the negative electrode active material is configured to discharge by the reaction expressed in Formula (2),
FeCO3+2e−→Fe+CO32-  (Formula 1)
Fe+CO32-→FeCO3+2e−  (Formula 2).