Patent Description:
<CIT> describes a battery pack including a housing which accommodates a battery and a control unit and a submersion sensor which detects a liquid fluid. The housing of the battery pack described in <CIT> includes a bottom wall and an annular side wall erected from the bottom wall, an accommodation space is formed by the bottom wall and the side wall so that a fluid can flow thereinto, the battery and the control unit are provided in the accommodation space, and at least a part of the submersion sensor detecting the submersion of the battery pack is disposed outside the accommodation space. In this way, in the battery pack described in <CIT>, the submersion sensor is provided outside the battery pack. <CIT> discloses a battery capable of detecting immersion and suspending charging and discharging.

However, in the technique described in <CIT>, since the submersion sensor is provided outside the battery pack, an installation space for providing the submersion sensor outside the battery pack is required. As a result, a problem arises in that the configuration becomes complicated.

This invention has been made in view of the above-described problems and an object of this invention is to provide a battery pack capable of detecting submersion of a battery case with a simple configuration.

According to aspects of this invention, which is given by the claims, there is provided a battery pack including:
a battery; and a battery case accommodating the battery, in which the battery case includes a first conductive portion and a second conductive portion formed of a conductive material and exposed to an outer surface, in which an insulating member insulating the first conductive portion and the second conductive portion is provided between the first conductive portion and the second conductive portion, and in which a first contact electrically connected to the first conductive portion, a second contact electrically connected to the second conductive portion, and a submersion detection circuit detecting an electrical connection between the first contact and the second contact caused by the submersion of the first conductive portion and the second conductive portion are provided inside the battery case.

In this way, according to this invention, it is possible to provide a battery pack capable of detecting submersion of a battery case with a simple configuration.

A battery pack according to embodiments of this invention includes: a battery; and a battery case accommodating the battery, in which the battery case includes a first conductive portion and a second conductive portion formed of a conductive material and exposed to an outer surface, in which an insulating member insulating the first conductive portion and the second conductive portion is provided between the first conductive portion and the second conductive portion, and in which a first contact electrically connected to the first conductive portion, a second contact electrically connected to the second conductive portion, and a submersion detection circuit detecting an electrical connection between the first contact and the second contact caused by the submersion of the first conductive portion and the second conductive portion are provided inside the battery case. Accordingly, the battery pack according to embodiments of this invention can detect the submersion of the battery case with a simple configuration.

A battery pack of a vehicle according to a first embodiment of this invention will be described with reference to the drawings. <FIG> is a view showing the battery pack according to the first embodiment of this invention.

In <FIG>, a battery pack <NUM> includes a high-voltage battery <NUM> and a battery case <NUM> accommodating the high-voltage battery <NUM>. The battery pack <NUM> is configured as an in-vehicle battery pack mounted in a vehicle such as an automobile (not shown), and supplies electric power to a driving motor provided in the vehicle via an inverter or the like.

The high-voltage battery <NUM> includes a plurality of battery cells 3A, a relay 3B which switches the connection of the plurality of battery cells 3A, and a lead wire 3C which connects the battery cell 3A and the relay 3B and is drawn out of the battery case <NUM>. The high-voltage battery <NUM> generates a high voltage by connecting the plurality of battery cells 3A in series with the lead wire 3C. The high-voltage battery <NUM> constitutes the battery of this invention.

The battery case <NUM> includes an upper casing <NUM> and a lower casing <NUM> which are joined together to form a sealed space that accommodates the high-voltage battery <NUM>. The upper casing <NUM> and the lower casing <NUM> constitute a casing body <NUM> which accommodates the high-voltage battery <NUM>. The upper casing <NUM> constitutes the first casing and the first conductive portion of this invention and the lower casing <NUM> constitutes the second casing and the second conductive portion of this invention.

The upper casing <NUM> and the lower casing <NUM> are formed of a conductive material and are exposed to the outer surface. As the conductive material, for example, metal such as iron can be used. Additionally, the outer surfaces of the upper casing <NUM> and the lower casing <NUM> may be coated with a non-conductive material if at least a part of the upper casing <NUM> and at least a part of the lower casing <NUM> are exposed to the outer surface.

An insulating member <NUM> for electrically insulating the upper casing <NUM> and the lower casing <NUM> is provided at the joint between the upper casing <NUM> and the lower casing <NUM>. Further, a seal member <NUM> is provided between the upper casing <NUM> and the lower casing <NUM> to liquid-tightly join the upper casing <NUM> and the lower casing <NUM>.

A first contact <NUM> electrically connected to the upper casing <NUM> and a second contact <NUM> electrically connected to the lower casing <NUM> are provided inside the battery case <NUM>. In this embodiment, the first contact <NUM> is connected to the inner wall surface (lower surface) of the upper casing <NUM> and the second contact <NUM> is connected to the inner wall surface of the lower casing <NUM> on the front side.

A submersion detection circuit <NUM> is provided inside the battery case <NUM>. The submersion detection circuit <NUM> is electrically connected to the first contact <NUM> via a lead wire 4A and is electrically connected to the second contact <NUM> via a lead wire 5A.

The submersion detection circuit <NUM> detects the electrical connection between the first contact <NUM> and the second contact <NUM> caused by the submersion of the upper casing <NUM> and the lower casing <NUM>.

In the battery pack <NUM> with such a configuration, when the upper casing <NUM> and the lower casing <NUM> formed of a conductive material are submerged, the upper casing <NUM> and the lower casing <NUM> are electrically connected to each other through water to have the same potential and the first contact <NUM> and the second contact <NUM> are also electrically connected to each other to have the same potential. Therefore, the submersion detection circuit <NUM> can determine that the battery case <NUM> has been submerged under the condition that the first contact <NUM> and the second contact <NUM> are electrically connected.

As described above, in this embodiment, the battery case <NUM> includes the upper casing <NUM> and the lower casing <NUM> which are formed of a conductive material and are exposed to the outer surface and the insulating member <NUM> insulating the upper casing <NUM> and the lower casing <NUM> is provided between the upper casing <NUM> and the lower casing <NUM>. Further, the first contact <NUM> electrically connected to the upper casing <NUM>, the second contact <NUM> electrically connected to the lower casing <NUM>, and the submersion detection circuit <NUM> detecting the electrical connection between the first contact <NUM> and the second contact <NUM> caused by the submersion of the upper casing <NUM> and the lower casing <NUM> are provided inside the battery case <NUM>.

Accordingly, it is possible to detect the submersion of the battery case <NUM> without providing a submersion sensor outside the battery case <NUM> by detecting the electrical connection between the first contact <NUM> and the second contact <NUM> caused by the submersion of the upper casing <NUM> and the lower casing <NUM> of the battery case <NUM>. As a result, the submersion of the battery case <NUM> can be detected with a simple configuration.

Further, in this embodiment, the battery case <NUM> includes the upper casing <NUM> which is the first conductive portion and the lower casing <NUM> which is the second conductive portion and these casings are joined to each other to form a closed space accommodating the high-voltage battery <NUM>. Then, the insulating member <NUM> is provided at the joint between the upper casing <NUM> and the lower casing <NUM>.

Accordingly, the first conductive portion and the second conductive portion can be respectively configured by using the upper casing <NUM> and the lower casing <NUM> generally provided in the battery case <NUM>. Therefore, it is possible to detect the submersion of the battery case <NUM> with a simple configuration.

A battery pack of a vehicle according to a second embodiment of this invention will be described with reference to the drawings. <FIG> and <FIG> are views showing the battery pack according to the second embodiment of this invention. Additionally, the same members as in the first embodiment will be described with the same reference numerals as in the first embodiment.

In <FIG> and <FIG>, abattery pack 1A includes the high-voltage battery <NUM> and abattery case 2A which accommodates the high-voltage battery <NUM>.

The battery case 2A includes the upper casing <NUM> and the lower casing <NUM> which are joined to each other to form a closed space accommodating the high-voltage battery <NUM>. The upper casing <NUM> and the lower casing <NUM> constitute the casing body <NUM> accommodating the high-voltage battery <NUM>.

The battery case 2A includes a vent <NUM> which is opened to the wall surface of the casing body <NUM> and adjusts the inner pressure of the casing body <NUM> and a filter member <NUM> that is provided in the vent <NUM> and prevents dusts from entering the casing body <NUM> from the vent <NUM>. The filter member <NUM> constitutes the first conductive portion of this invention and the casing body <NUM> constitutes the second conductive portion of this invention.

The filter member <NUM> and the casing body <NUM> are formed of a conductive material and are exposed to the outer surface. The seal member <NUM> is provided at the joint between the upper casing <NUM> and the lower casing <NUM>. The vent <NUM> has a square shape and is disposed on the wall surface of the lower casing <NUM> of the casing body <NUM> on the front side. The filter member <NUM> is made of a mesh filter in which fine wires of metal such as iron are formed in a mesh shape. Additionally, in this embodiment, the vent <NUM> and the filter member <NUM> are provided on the wall surface of the lower casing <NUM> in the casing body <NUM>, but the vent <NUM> and the filter member <NUM> may be provided on the wall surface of the upper casing <NUM> instead of the lower casing <NUM>.

An insulating member <NUM> electrically insulating the filter member <NUM> and the casing body <NUM> is provided at the joint between the filter member <NUM> and the casing body <NUM>.

The first contact <NUM> electrically connected to the filter member <NUM> and the second contact <NUM> electrically connected to the casing body <NUM> are provided inside the battery case 2A. In this embodiment, the first contact <NUM> is connected to the edge portion of the filter member <NUM> and the second contact <NUM> is connected to the inner wall surface of the lower casing <NUM> of the casing body <NUM> on the front side.

The submersion detection circuit <NUM> is provided inside the battery case 2A. The submersion detection circuit <NUM> is electrically connected to the first contact <NUM> via the lead wire 4A and is electrically connected to the second contact <NUM> via the lead wire 5A.

The submersion detection circuit <NUM> detects the electrical connection between the first contact <NUM> and the second contact <NUM> caused by the submersion of the filter member <NUM> and the casing body <NUM>.

In the battery pack 1A with such a configuration, when the filter member <NUM> and the casing body <NUM> formed of a conductive material are submerged, the filter member <NUM> and the casing body <NUM> are electrically connected to each other through water to have the same potential and the first contact <NUM> and the second contact <NUM> are also electrically connected to each other to have the same potential. Therefore, the submersion detection circuit <NUM> can determine that the battery case 2A has been submerged under the condition that the first contact <NUM> and the second contact <NUM> are electrically connected.

Additionally, it is preferable that a partition wall <NUM> indicated by a dashed line in <FIG> and <FIG> is provided inside the casing body <NUM> to suppress water from entering through the vent <NUM>. The partition wall <NUM> is disposed inside the vent <NUM> in the casing body <NUM> and is formed in a U-shape in the plan view or an L-shape in the side view. The partition wall <NUM> covers the bottom surface and the side surface of the inner space of the vent <NUM> and the filter member <NUM>. Accordingly, air inside the casing body <NUM> passes above the partition wall <NUM> to reach the vent <NUM> and exit to the outside as indicated by an arrow A (see <FIG>). Conversely, the air that has entered from the outside of the casing body <NUM> through the vent <NUM> can enter further inside while passing above the partition wall <NUM>.

As described above, in this embodiment, the battery case 2A includes the filter member <NUM> and the casing body <NUM> formed of a conductive material and exposed to the outer surface and the insulating member <NUM> insulating the filter member <NUM> and the casing body <NUM> is provided between the filter member <NUM> and the casing body <NUM>. Then, the first contact <NUM> electrically connected to the filter member <NUM>, the second contact <NUM> electrically connected to the casing body <NUM>, and the submersion detection circuit <NUM> detecting the electrical connection between the first contact <NUM> and the second contact <NUM> caused by the submersion of the filter member <NUM> and the casing body <NUM> are provided inside the battery case 2A.

Accordingly, it is possible to detect the submersion of the battery pack 1A without providing the submersion sensor outside the battery case 2A by detecting the electrical connection between the first contact <NUM> and the second contact <NUM> caused by the submersion of the casing body <NUM> and the filter member <NUM> of the battery case 2A. As a result, it is possible to detect the submersion of the battery case 2A with a simple configuration.

Further, in this embodiment, the battery case 2A includes the casing body <NUM> which is the second conductive portion accommodating the high-voltage battery <NUM>, the vent <NUM> which is opened to the wall surface of the casing body <NUM> and adjusts the inner pressure of the casing body <NUM>, and the filter member <NUM> that is provided in the vent <NUM> and is the first conductive portion preventing dust from entering the casing body <NUM> from the vent <NUM>. Then, the insulating member <NUM> is provided at the joint between the filter member <NUM> and the casing body <NUM>.

Accordingly, the first conductive portion and the second conductive portion can be respectively configured by using the casing body <NUM> and the vent <NUM> which are the members generally provided in the battery case 2A. Therefore, it is possible to detect the submersion of the battery case 2A with a simple configuration.

While embodiments of this invention have been described, it is apparent that some artisan could have made changes without departing from the scope of this invention. It is intended that any and all such modifications are involved in the appended claims.

Claim 1:
A battery pack (<NUM>, 1A) comprising:
a battery (<NUM>); and
a battery case (<NUM>, 2A) accommodating the battery (<NUM>),
wherein the battery case (<NUM>, 2A) includes a first conductive portion (<NUM>, <NUM>) and a second conductive portion (<NUM>, <NUM>) formed of a conductive material and exposed to an outer surface,
wherein an insulating member (<NUM>, <NUM>) insulating the first conductive portion (<NUM>, <NUM>) and the second conductive portion (<NUM>, <NUM>) is provided between the first conductive portion (<NUM>, <NUM>) and the second conductive portion (<NUM>, <NUM>), and
wherein a first contact (<NUM>) electrically connected to the first conductive portion (<NUM>, <NUM>), a second contact (<NUM>) electrically connected to the second conductive portion (<NUM>, <NUM>), and a submersion detection circuit (<NUM>) detecting an electrical connection between the first contact (<NUM>) and the second contact (<NUM>) caused by the submersion of the first conductive portion (<NUM>, <NUM>) and the second conductive portion (<NUM>, <NUM>) are provided inside the battery case (<NUM>, 2A).