Battery pack and method of controlling the same

Patent metadata

Field	Value
Publication number	US-9484763-B2
Application number	US-201313826479-A
Country	US
Kind code	B2
Filing date	Mar 14, 2013
Priority date	Oct 16, 2012
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A battery pack and a method of controlling the same. The battery pack includes: a first battery module that includes at least one battery cell; a second battery module that includes at least one battery cell electrically connected to the first battery module; a charge/discharge control unit that breaks or connects a charge/discharge path of each of the first battery module and the second battery module; a first battery management unit that controls the first battery module; and a second battery management unit that generates a signal for controlling switches included in the charge/discharge control unit by referring to a state of the second battery module, wherein the first battery management unit and the second battery management unit are connected in parallel to the charge/discharge control unit.

First claim

What is claimed is:

1. A battery pack comprising:
a first battery module that comprises at least one battery cell;
a second battery module that comprises at least one battery cell electrically connected to the first battery module;
a charge/discharge control unit that comprises a charge control switch and a discharge control switch to break or connect a charge/discharge path of each of the first battery module and the second battery module;
a first battery management unit that controls the first battery module and that generates a signal for directly controlling the charge control switch or the discharge control switch by referring to a state of the first battery module only; and
a second battery management unit that generates a signal for controlling the charge control switch or the discharge control switch through switch elements connected to the second battery management unit by referring to a state of the second battery module only,
wherein the first battery management unit and the second battery management unit are connected in parallel to the charge/discharge control unit,
wherein, when battery cells, a number of which exceeds a maximum number of battery cells that can be managed by the first battery management unit, are required, the second battery module is a set of surplus battery cells added to the first battery module.

2. The battery pack of claim 1 , wherein the second battery management unit comprises:
a cell control unit that determines whether there is a risk of overcharge or over discharge by detecting a state of each of the at least one battery cell included in the second battery module; and
a first switch and a second switch that operate by receiving a signal from the cell control unit.

3. The battery pack of claim 2 , wherein the second battery management unit generates a signal for turning on the first switch when there is a risk of over discharge in the at least one battery cell included in the second battery module.

4. The battery pack of claim 3 , wherein when the first switch is turned on, a third switch that is connected to the first switch and is included in the charge/discharge control unit is turned on and the discharge control switch that is connected to the third switch is turned off.

5. The battery pack of claim 2 , wherein the second battery management unit generates a signal for turning on the second switch when there is a risk in the at least one battery cell included in the second battery module.

6. The battery pack of claim 5 , wherein when the second switch is turned on, a fourth switch that is connected to the second switch and is included in the charge/discharge control unit is turned on and the charge control switch that is connected to the fourth switch is turned off.

7. The battery pack of claim 2 , wherein the second battery management unit generates a signal for turning off the first switch or the second switch when the at least one battery cell included in the second battery module is in a normal state with no risk of overcharge or over discharge.

8. The battery pack of claim 7 , wherein when the first switch is turned off, a third switch that is connected to the first switch and is included in the charge/discharge control unit is turned off and the discharge control switch that is connected to the third switch is turned on.

9. The battery pack of claim 7 , wherein when the second switch is turned off, a fourth switch that is connected to the second switch and is included in the charge/discharge control unit is turned off and the charge control switch that is connected to the fourth switch is turned on.

10. The battery pack of claim 2 , wherein the cell control unit determines whether there is a risk of overcharge or over discharge in the at least one battery cell included in the second battery module by comparing a state of charge (SOC) of each of the at least one battery cell with a reference state of charge (SOC).

11. The battery pack of claim 1 , wherein the first battery management unit comprises:
an analog front end that converts an analog value about a state of the first battery module into a digital value; and
a microprocessor that transmits a signal to the charge/discharge control unit;
a memory that stores a setting value of the microprocessor.

12. The battery pack of claim 1 , wherein when the charge and discharge control switches included in the charge/discharge control unit are metal-oxide semiconductor field-effect transistors (MOSFETs), the charge/discharge control unit comprises a resistor for adjusting a voltage applied to gates of the charge and discharge control switches.

13. A battery pack comprising:
a first battery module that comprises at least one battery cell;
a second battery module that comprises at least one battery cell electrically connected to the first battery module;
a protection circuit that controls charge/discharge of the first battery module and the second battery module; and
a terminal unit that connects the first battery module and the second battery module to an external device. wherein the protection circuit comprises:
a charge/discharge control unit that breaks or connects a charge/discharge path of each of the first battery module and the second battery module;
a first battery management unit that detects a state of the first battery module only and that controls the charge/discharge the first battery module; and
a second battery management unit that generates a signal for controlling switches included in the charge/discharge control unit by referring to a state of the second battery module only,
wherein, when battery cells, a number of which exceeds a maximum number of battery cells that can be managed by the first battery management unit, are required, the second battery module is a set of surplus battery cells added to the first battery module.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Kim Bong-Young
• Shin Ki-Ho

Classifications

• H02J7/575

  Parallel/serial switching of connection of batteries to charge or load circuit · CPC title

• H02J7/52 Primary

  for charge balancing, e.g. equalisation of charge between batteries · CPC title

• H02J7/90 Primary

  Regulation of charging or discharging current or voltage · CPC title

• H02J7/0024

  Electricity · mapped topic

• H02J7/007 Primary

  Electricity · mapped topic