Battery system and motor vehicle having a battery system

A battery system, comprising:

• a plurality of battery cells arranged in a battery housing, wherein a respective battery cell has a cell housing at least partly surrounding a galvanic cell, wherein the cell housing and/or the battery housing have/has at least one degassing opening, which is designed to let a stream of gas escape from an interior of the cell housing and/or the battery housing along a predetermined degassing path into the surroundings of the battery cell and/or the battery system, wherein a spark arrester is arranged along the predetermined degassing path and designed to filter sparks and/or particles from the stream of gas, wherein the spark arrester is designed to reduce a flow rate of the stream of gas relative to an initial rate and to direct the stream of gas along a surface of the spark arrester, so that the stream of gas flows along the surface at least for a predetermined period of time, wherein the period of time, the surface, and the reduced flow rate are matched to one another such that thermal output energy is extracted from the stream of gas to the extent that a temperature of the stream of gas when escaping into the surroundings has dropped to a value below a predetermined limit temperature value.