Thermal management of battery systems

A battery system has a plurality of battery cells including a first battery cell. Each battery cell includes a casing enclosing an anode and a cathode. The battery system also includes a first fluid circulation system with a plurality of fluid conduits including a first fluid conduit that is adjacent to the first battery cell, where the first fluid circulation system is configured to circulate a first fluid through the battery system in a first direction. The battery system also includes a second fluid circulation system with a plurality of fluid conduits including a first fluid conduit that is adjacent to the first fluid conduit of the first fluid circulation system. The second fluid circulation system is configured to circulate a second fluid through the battery system in a second direction that is opposite the first direction.