Borate oxalate
The borate oxalates are chemical compounds containing borate and oxalate anions. Where the oxalate group is bound to the borate via oxygen, a more condensed anion is formed that balances less cations. These can be termed boro-oxalates, bisborates, or oxalatoborates or oxalate borates. The oxalatoborates are heterocyclic compounds with a ring containing -O-B-O-. Bisborates are spiro compounds with rings joined at the boron atom.
Oxalatoborates are used or for research in lithium-ion battery electrolytes and for supercapacitors.