# US 12,015,288 B2 · Electrical energy storage device

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,015,288 B2
- Document ID: US12015288B2
- Status: Granted
- Kind: B2
- Application number: 17/395,859
- Filed: 2021-08-06
- Published: 2022-02-10
- Granted: 2024-06-18
- Earliest claimed: 2020-08-07
- Assignees: Honda Motor Co., Ltd.
- Applicants: Honda Motor Co., Ltd.
- Inventors: Koji Saotome
- Web page: https://patentgrep.com/patent/US12015288B2

## CPC

- H02J 7/54: Passive balancing, e.g. using resistors or parallel MOSFETs
- B60L 58/22: Balancing the charge of battery modules
- G01R 31/382: Arrangements for monitoring battery or accumulator variables, e.g. SoC
- H01F 27/2804: {Printed windings}
- H01F 27/2809: {on stacked layers}
- H01F 38/14: Inductive couplings
- H01M 10/425: {Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing (printed circuits H05K1/00)}
- H01M 10/441: {for several batteries or cells simultaneously or sequentially}
- H01M 10/482: {for several batteries or cells simultaneously or sequentially}
- H01M 50/204: Racks, modules or packs for multiple batteries or multiple cells
- H02J 7/56: Active balancing, e.g. using capacitor-based, inductor-based or DC-DC converters
- H01M 50/209: adapted for prismatic or rectangular cells (H01M50/216 takes precedence)
- H01M 2010/4271: {Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing}
- Y02E 60/10: Energy storage using batteries
- Y02T 10/70: Energy storage systems for electromobility, e.g. batteries
- H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

An electrical energy storage device is constituted by connecting together a plurality of battery cells. Each of the battery cells includes a transformer forming unit constituted by a first inductor, a second inductor, a first core member, and a second core member, and which is capable of forming a transformer between itself and an adjacent battery cell, and a potential detection unit that detects the potential of the battery cell. A control unit compares the potentials of the adjacent battery cells based on measurement results of a potential detection unit. Furthermore, the control unit performs an equalization control to equalize the potentials of the plurality of battery cells, by supplying electrical charge from the battery cell having a higher potential to the battery cell having a lower potential.

## Claims

### Claim 1

An electrical energy storage device comprising a plurality of battery cells connected together;
each of the plurality of battery cells comprising:
a transformer forming unit including an inductor and a core member, and configured to form a transformer between the transformer forming unit itself and an inductor and a core member of an adjacent battery cell; and
a potential detection unit configured to detect a potential of the battery cell;
the electrical energy storage device further comprising a control unit configured to control an energized state of the inductor in each of the plurality of battery cells;
wherein the control unit compares the potentials of the adjacent battery cells based on measurement results of the potential detection unit, and via the transformer in which the inductor of a battery cell having a higher potential is made to serve as a primary side inductor and the inductor of another battery cell having a lower potential is made to serve as a secondary side inductor, performs an equalization control to equalize the potentials of the plurality of battery cells, by supplying electrical charge from the battery cell having the higher potential to the battery cell having the lower potential;
each of the plurality of battery cells comprises a main body configured to charge and discharge the electrical charge;
the transformer forming unit is formed in a plate shape, and is arranged between adjacent ones of the main bodies;
in the inductor, windings are configured along a planar direction of a side surface of the main body;
the core member extends along the side surface, and is formed in a sheet shape so as to accommodate the inductor on an inner side thereof; and
the core member includes a central portion that is in contact with another core member of the adjacent battery cell, at a center of the inductor, and an outer side portion that is in contact with the other core member of the adjacent battery cell, on an outer side of the inductor.

### Claim 2 (depends on 1)

The electrical energy storage device according to claim 1, wherein each of the plurality of battery cells comprises a support member configured to support the transformer forming unit and the potential detection unit, and having conductive paths for the transformer forming unit and the potential detection unit.

### Claim 3

An electrical energy storage device comprising a plurality of battery cells connected together;
each of the plurality of battery cells comprising:
a transformer forming unit including an inductor and a core member, and configured to form a transformer between the transformer forming unit itself and an inductor and a core member of an adjacent battery cell; and
a potential detection unit configured to detect a potential of the battery cell;
the electrical energy storage device further comprising a control unit configured to control an energized state of the inductor in each of the plurality of battery cells;
wherein the control unit compares the potentials of the adjacent battery cells based on measurement results of the potential detection unit, and via the transformer in which the inductor of a battery cell having a higher potential is made to serve as a primary side inductor and the inductor of another battery cell having a lower potential is made to serve as a secondary side inductor, performs an equalization control to equalize the potentials of the plurality of battery cells, by supplying electrical charge from the battery cell having the higher potential to the battery cell having the lower potential;
each of the plurality of battery cells comprises a support member configured to support the transformer forming unit and the potential detection unit, and having conductive paths for the transformer forming unit and the potential detection unit;
the support member includes a first site disposed on one side surface of the battery cell, a second site disposed on a side surface on an opposite side from the one side surface of the battery cell, and a third site disposed on an upper surface of the battery cell and configured to connect the first site and the second site;
the transformer forming unit is disposed on the first site or the second site; and
the potential detection unit is disposed on the third site.

### Claim 4 (depends on 1)

The electrical energy storage device according to claim 1, further comprising:
a switching circuit configured to turn on and turn off flow of electric current with respect to the inductor;
wherein, when performing the equalization control, the control unit maintains a time ratio, which is a ratio of an on-time period during which electric current is supplied to the inductor by the switching circuit, constant.

### Claim 5 (depends on 1)

The electrical energy storage device according to claim 1, further comprising:
a switching circuit configured to turn on and turn off flow of electric current with respect to the inductor;
wherein, when performing the equalization control, the control unit increases a time ratio, which is a ratio of an on-time period during which electric current is supplied to the inductor by the switching circuit, as a potential difference between the adjacent battery cells grows larger.

### Claim 6 (depends on 1)

The electrical energy storage device according to claim 1, wherein:
the control unit calculates a potential difference of the plurality of battery cells based on measurement results of the potential detection unit, and compares a previously retained allowable potential range with the calculated potential difference; and
the control unit performs the equalization control in a case that the calculated potential difference is greater than the allowable potential range; and
while on the other hand, does not perform the equalization control in a case that the calculated potential difference is less than or equal to the allowable potential range.

### Claim 7 (depends on 1)

The electrical energy storage device according to claim 1, wherein the control unit stores in advance a limited range of potentials within which the battery cells do not become in a state of excessive voltage or excessive discharging; and
the control unit performs the equalization control amongst battery cells having potentials within the limited range, and while on the other hand, in a case that a battery cell is recognized having a potential outside of the limited range, the control unit does not perform the equalization control on that battery cell.

### Claim 8 (depends on 1)

The electrical energy storage device according to claim 1, wherein each of the plurality of battery cells comprises a communication unit configured to carry out wireless communication with the control unit.