In a battery apparatus, a battery pack includes a plurality of battery modules and a bus-bar connecting two battery modules among the plurality of battery modules. A wire connects the battery pack and the switch for controlling current supply of the battery pack. A voltage measuring circuit measures a voltage of the bus-bar, a voltage of the battery pack, and voltages of the plurality of battery modules. A processor diagnoses a connection status of the bus-bar and a connection status of the wire based on a current of the battery pack, the voltage of the bus-bar, the voltage of the battery pack, and the voltages of the plurality of battery modules.

In a battery apparatus, a battery pack includes a plurality of battery modules and a bus-bar connecting two battery modules among the plurality of battery modules. A wire connects the battery pack and the switch for controlling current supply of the battery pack. A voltage measuring circuit measures a voltage of the bus-bar, a voltage of the battery pack, and voltages of the plurality of battery modules. A processor diagnoses a connection status of the bus-bar and a connection status of the wire based on a current of the battery pack, the voltage of the bus-bar, the voltage of the battery pack, and the voltages of the plurality of battery modules.

A battery module includes: a battery cell stack in which a plurality of battery cells are stacked; a module frame for accommodating the battery cell stack; and an end plate for covering the front and rear surfaces of the battery cell stack, wherein an opening is formed between the module frame bottom portion and the end plate.

A bus bar includes a wiring pathway made from a conductive material and having bent portions bending at at least two sites of the wiring pathway. The wiring pathway includes members consecutively arranged to form a plate shape. At least two of the members have different characteristics. The members adjacent to each other are connected to each other by laser joining.

A bus bar includes members made from a conductive material and consecutively arranged to form a plate shape defining a wiring pathway. The members adjacent to each other are connected to each other by laser joining. The members include connection members arranged at both ends of the wiring pathway and having connection portions for electrical input-output, and a conductive member arranged between the connection members. In the members, only the connection members are plated.

A bus bar includes members made from a conductive material and consecutively arranged to form a plate shape defining a wiring pathway. The members adjacent to each other have connection surfaces at which the members adjacent to each other are connected to each other by laser joining. The members adjacent to each other include at least one tolerance buffer between the members adjacent to each other. In the at least one tolerance buffer, the connection surfaces of the members adjacent to each other have different widths.

The present disclosure provides a secondary battery which comprises: a cap plate provided with a first electrode terminal; an electrode assembly comprising a main body and a first electrode tab; a first connecting piece connected between the first electrode tab and the first electrode terminal. The first connecting piece includes a first electrode terminal connecting portion, a first electrode tab connecting portion and a first fusing portion. The secondary battery further comprises an insulating piece arranged on the first connecting piece to prevent direct physical contact between the first electrode tab and the first electrode terminal connecting portion by covering at least an edge of the first electrode terminal connecting portion.

The present disclosure provides a secondary battery which comprises: a cap plate provided with a first electrode terminal; an electrode assembly comprising a main body and a first electrode tab; a first connecting piece connected between the first electrode tab and the first electrode terminal. The first connecting piece includes a first electrode terminal connecting portion, a first electrode tab connecting portion and a first fusing portion. The secondary battery further comprises an insulating piece arranged on the first connecting piece to prevent direct physical contact between the first electrode tab and the first electrode terminal connecting portion by covering at least an edge of the first electrode terminal connecting portion.

A battery module according to an exemplary embodiment of the present invention includes: a housing receiving a plurality of battery cells and including a bottom plate and a lateral plate; and a connection board disposed at one end or both ends of the housing, wherein the connection board is bonded to the lateral plate. The lateral plate may include a plurality of bus bar supporting members, at least some among the plurality of bus bar supporting members having a hooking protrusion protruded upward. The connection board may include a hooking member having a hooking groove opened downward. Thus, the hooking protrusion may be inserted into the hooking groove in a state in which the connection board is bonded to the lateral plate.

A battery module according to an exemplary embodiment of the present invention includes: a housing receiving a plurality of battery cells and including a bottom plate and a lateral plate; and a connection board disposed at one end or both ends of the housing, wherein the connection board is bonded to the lateral plate. The lateral plate may include a plurality of bus bar supporting members, at least some among the plurality of bus bar supporting members having a hooking protrusion protruded upward. The connection board may include a hooking member having a hooking groove opened downward. Thus, the hooking protrusion may be inserted into the hooking groove in a state in which the connection board is bonded to the lateral plate.