The invention relates to a device for storing and delivering an aqueous additive for catalytic exhaust-gas denitrogenization in a motor vehicle. The device comprises a storage vessel (1) enclosing a storage volume (2), comprises at least one delivery pump (8) for the additive, and comprises means for heating at least parts of the storage volume (2), wherein the device is characterized in that the storage vessel (1) is at least partially of double-walled form.