Battery pack, battery apparatus including the same, and cell balancing method thereof

• US 9,419,466 B2
• Filed: 01/23/2013
• Issued: 08/16/2016
• Est. Priority Date: 08/24/2012
• Status: Active Grant

• Current Assignee: SNU R&DB Foundation (Seoul National University)
• Original Assignee: SNU R&DB Foundation (Seoul National University)
• Inventors: Lee, Jung Woo
• Primary Examiner(s): Ngo, Brian
• Application Number:
  US13/747,850
• Publication Number:
  US 20140055096A1
• Time in Patent Office: 1,301 Days
• Field of Search: 320/108, 320/134, 320/137, 320/158, 320/159, 320/162
• US Class Current: 1/1
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A battery pack includes: a cell module including a plurality of battery cells; and a coil unit installed on one side of the cell module and having coils stacked therein, the coils being connected to the respective battery cells.

Claims

1. A battery apparatus comprising:

a cell module comprising a plurality of battery cells;

a coil unit installed on one side of the cell module and having coils stacked therein, the coils being connected to the respective battery cells; and

a battery management system (BMS) configured to select a transmitting cell and one or more receiving cells based on states of charge (SOC) of the respective cells, and form an induced current in a coil connected to the transmitting cell by converting electric charges discharged from the transmitting cell into AC current, and converting the induced current induced into one or more coils connected to the one or more receiving cells into DC power,

wherein the BMS comprises a cell management unit configured to manage IDs of the respective cells;

a voltage sensor configured to measure the SOC of each of the battery cells;

a cell selection unit configured to select a transmitting cell and one or more receiving cells based on the measurement result of the voltage sensor, when cell balancing is required; and

a path control unit connected between each battery cell and a coil connected to the battery cell, and configured to form a current path such that the coil connected to the transmitting cell and the coils connected to the one or more receiving cells cause magnetic induction therebetween,

wherein the path control unit comprises a first switch connected to a first electrode of a battery cell;

a DC-to-AC converter connected to the first switch;

a third switch connected to the DC-to-AC converter and turned on or off in connection with the first switch;

a second switch connected to the first electrode of the battery cell in parallel to the first switch;

an AC-to-DC converter connected to the second switch; and

a fourth switch connected to the AC-to-DC converter, turned on or off in connection with the second switch, and having one end connected to one end of the third switch.

2. The battery apparatus according to claim 1, wherein the cell selection unit selects a cell having the highest SOC as the transmitting cell.

3. The battery apparatus according to claim 1, wherein the cell selection unit selects the receiving cells by a designated number of receiving cells from a cell having the lowest SOC.

4. The battery apparatus according to claim 1, wherein a coil connected to the battery cell has one side connected to a second electrode of the battery cell and the other side connected to a common connection terminal of the third and fourth switches.