TECHNICAL FIELD
The present disclosure relates to a battery module having a cooling structure using
insulating oil and a battery pack and a vehicle including the battery module, and more
10 particularly, to a battery module having a structure in which insulating oil introduced into a
module housing flows through a space between an edge of a battery cell and the module
housing to cool battery cells, and a battery pack and a vehicle including the battery module.
The present application claims priority to Korean Patent Application No. 10-2020-
0153017 filed on November 16, 2020 in the Republic of Korea, the disclosures of which are
15 incorporated herein by reference.
BACKGROUND ART
In the case of a battery module using an indirect water cooling method using cooling
water, because cooling water does not directly contact a battery cell but indirectly contacts
20 the battery cell through a module housing in which the battery cell is accommodated, there
is a limit to its cooling performance. Also, because a cooling device such as a separate heat
sink should be provided outside the module housing to form a passage for cooling, a volume
of the battery module is inevitably increased, which may cause loss in terms of energy
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density.
In order to solve the problems of the indirect water cooling method, there is a need
to develop a battery module having a cooling structure in which insulating oil for cooling
may be directly introduced into a module housing and may directly contact a battery cell.
5 In the case of a battery module having a direct cooling structure using insulating oil,
it is very important to secure a fluid passage structure for efficient cooling, and maintain
airtightness so that insulating oil does not leak to the outside of a module housing.
DISCLOSURE
10 Technical Problem
The present disclosure is designed to solve the problems of the related art, and
therefore the present disclosure is directed to securing a path so that insulating oil introduced
into a module housing smoothly flows in a longitudinal direction of a battery module.
However, the technical purpose to be solved by the present disclosure is not limited
15 to the above, and other objects not mentioned herein will be clearly understood by one of
ordinary skill in the art from the following disclosure.
Technical Solution
In one aspect of the present disclosure, there is provided a battery module including:
20 a sub-module including a cell stack assembly including a plurality of battery cells and a
cooling fin located between adjacent battery cells, a front bus bar frame coupled to a side of
the cell stack assembly in a longitudinal direction of the cell stack assembly, and a rear bus
bar frame coupled to the other side of the cell stack assembly in the longitudinal direction of
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the cell stack assembly; a module housing including a main housing in which the sub-module
is accommodated, a lower cover covering a lower opening portion of the main housing, and
an upper cover covering an upper opening portion of the main housing; an insulating oil inlet
passing through a side of the main housing in a longitudinal direction of the main housing
5 and configured to supply insulating oil into a receiving space of the sub-module; and an
insulating oil outlet passing through the other side of the main housing in the longitudinal
direction of the main housing and configured to discharge outward the insulating oil from
the receiving space of the sub-module.

WHAT IS CLAIMED IS:
1. A battery module comprising:
a sub-module comprising a cell stack assembly comprising a plurality of battery
5 cells and a cooling fin located between adjacent battery cells, a front bus bar frame coupled
to a side of the cell stack assembly in a longitudinal direction of the cell stack assembly, and
a rear bus bar frame coupled to the other side of the cell stack assembly in the longitudinal
direction of the cell stack assembly;
a module housing comprising a main housing in which the sub-module is
10 accommodated, a lower cover covering a lower opening portion of the main housing, and an
upper cover covering an upper opening portion of the main housing;
an insulating oil inlet passing through a side of the main housing in a longitudinal
direction of the main housing and configured to supply insulating oil into a receiving space
of the sub-module; and
15 an insulating oil outlet passing through the other side of the main housing in the
longitudinal direction of the main housing and configured to discharge outward the
insulating oil from the receiving space of the sub-module.
2. The battery module of claim 1, wherein the cooling fin comprises:
20 a body contact portion located between adjacent battery cells; and
a pair of edge cover portions bent at an upper end and a lower end of the body contact
portion to cover edges of the battery cell.
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3. The battery module of claim 2, wherein an insulating oil passage for guiding
a flow of the insulating oil is formed between the upper cover and an edge of the battery cell,
between the lower cover and an edge of the battery cell, and between an edge of the battery
cell and the edge cover portion.
5
4. The battery module of claim 3, wherein insulating oil introduced through
the insulating oil inlet into the module housing passes through the front bus bar frame and is
introduced into the insulating oil passage.
10 5. The battery module of claim 4, wherein the insulating oil passing through
the insulating oil passage passes through the rear bus bar frame and is discharged to outside
of the module housing through the insulating oil outlet.
6. The battery module of claim 1, further comprising a pair of terminal
15 assemblies electrically connected to the plurality of battery cells constituting the cell stack,
a part of the pair of terminal assemblies being exposed to outside of the module housing
through the upper cover.
7. The battery module of claim 6, wherein each of the pair of terminal
20 assemblies comprises:
an internal terminal fixed to the front bus bar frame, and connected to an electrode
lead of a battery cell located at an outermost position from among the battery cells provided
in the cell stack assembly;
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a terminal spacer inserted by passing through the upper cover; and
an external terminal connected to the internal terminal inside the module housing,
and passing through the terminal spacer and exposed to outside of the module housing.
5 8. The battery module of claim 7, wherein the upper cover comprises:
a spacer receiving groove into which the terminal spacer is inserted; and
a spacer insertion hole passing through a bottom surface of the spacer receiving
groove.