NOVELTY - The device (5) has a heating element (6) thermally coupled with a battery (1) that is formed from multiple single flat cells (2). The heating element comprises multiple heating units (6.2) that are arranged or integrated into a pliable cladding element (6.1). The heating units are arranged parallel to each other and run in a meander-like or zig-zag manner. The cladding element is made of a textile mat, a woven cloth or heat-proof threads. The cells are held by a support (4) and connected in series. Ends of the heating units are led out as a terminal (6.2.1) from the cladding element.    USE - Device for heating a battery such as high volt battery i.e. lithium ion battery, in a vehicle (all claimed) e.g. electric car and hybrid car.    ADVANTAGE - The heating element comprises the heating units that are arranged or integrated into the pliable cladding element, thus mounting the device in a flexible manner with reduced effort. The cladding element is formed from the textile mat or the woven cloth, so that the device has a simple, flat and flexible structure. The cladding element is formed from the heat-proof threads, thus improving safety of the cladding element. The device enables the battery to be operated at optimum temperature, so that requirement of additional components e.g. heater and heat exchanger, is avoided, thus manufacturing the device in a cost-effective manner with reduced effort while ensuring a compact structure to the device, and hence reducing installation space of the device.    DETAILED DESCRIPTION - The heating units are designed as heating wires, heating tapes, heating strands or fluid channels. An INDEPENDENT CLAIM is also included for a battery.    DESCRIPTION OF DRAWING(S) - The drawing shows an exploded perspective view of a battery with a mountable heating device.    Battery (1)    Single flat cells (2)    Support (4)    Device for heating battery (5)    Heating element (6)    Pliable cladding element (6.1)    Heating units (6.2)    Terminal (6.2.1)