Method and system for protection of a lithium-based multicell battery pack including a heat sink

• US 7,667,437 B2
• Filed: 02/17/2009
• Issued: 02/23/2010
• Est. Priority Date: 11/22/2002
• Status: Expired due to Term

• Current Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Original Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Inventors: Scheucher, Karl F., Kubale, Mark A., Johnson, Todd W., Glasgow, Kevin L., Rosenbecker, Jay J., Zeiler, Jeffrey M., Grzybowski, Dennis J., Meyer, Gary D.
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): Boateng; Alexis
• Application Number:
  US12/372,013
• Publication Number:
  US 20090195216A1
• Time in Patent Office: 371 Days
• Field of Search: 320/120, 320/132, 320/134, 320/150, 320/112, 320/113, 320/119
• US Class Current: 320/150
• CPC Class Codes: B25F 5/02 Construction of casings, bodies or handles B25F5/006, B25F5/008 take precedence
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• 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 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/623 Portable devices, e.g. mobile telephones, cameras or pacemakers
• CPC Class Codes: H01M 10/6235 Power tools
• CPC Class Codes: H01M 10/6551 Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings
• 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 2220/30 Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H01M 50/202 : Casings or frames around the primary casing of a single cell or a single battery
• CPC Class Codes: H01M 50/211 : adapted for pouch cells
• CPC Class Codes: H01M 50/213 : adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: H01M 50/247 : specially adapted for portable devices, e.g. mobile phones, computers, hand tools or pacemakers
• CPC Class Codes: H01M 50/284 : with incorporated circuit boards, e.g. printed circuit boards [PCB]
• CPC Class Codes: H01M 50/296 : characterised by terminals of battery packs terminals of batteries H01M50/543
• CPC Class Codes: H01M 50/569 : Constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals battery terminal connectors with integrated measuring arrangements G01R31/364
• CPC Class Codes: H02H 7/18 : for batteries; for accumulators
• CPC Class Codes: H02J 7/00 : Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00038 : using passive battery identification means, e.g. resistors or capacitors identification by mechanical connections H02J7/0045
• CPC Class Codes: H02J 7/00047 : with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0014 : Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0029 : with safety or protection devices or circuits
• CPC Class Codes: H02J 7/00309 : Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0031 : using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0042 : characterised by the mechanical construction
• CPC Class Codes: H02J 7/0045 : concerning the insertion or the connection of the batteries
• CPC Class Codes: H02J 7/0063 : with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/007 : Regulation of charging or discharging current or voltage
• CPC Class Codes: H02J 7/007182 : in response to battery voltage
• CPC Class Codes: H02J 7/007184 : in response to battery voltage gradient
• CPC Class Codes: H02J 7/007194 : of the battery
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries

Abstract

A system and method for battery protection. In some aspects, a battery pack includes a housing, a cell supported by the housing, a circuit supported by the housing and operable to control a function of the battery pack, and a heat sink in heat transfer relationship with the circuit and operable to dissipate heat from the circuit.

Claims

1. A Lithium-ion battery pack configured to be interfaced with a power tool, the battery pack comprising:

a housing;

a plurality of terminals;

a plurality of rechargeable Lithium-ion battery cells arranged within and supported by the housing, each of the battery cells having a respective state of charge, the battery pack having a state of charge, power being transferable between the battery cells and the power tool;

a control circuit operable to control a plurality of functions of the battery pack including discharging functions, the control circuit including a controller, the control circuit configured to control at least one function of the battery pack based on a monitored state of charge;

a switch configured, when open, to disable transfer of power between the battery cells and the power tool, the switch further configured, when closed, to enable transfer of power between the battery cells and the power tool, the switch including at least one field effect transistor (FET); and

a heat sink in heat transfer relationship with the switch and operable to dissipate heat from the switch.