METHODOLOGY FOR CHARGING BATTERIES SAFELY

• US 20170074918A1
• Filed: 11/22/2016
• Published: 03/16/2017
• Est. Priority Date: 06/08/2010
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Motors Incorporated (Tesla Inc.)
• Inventors: Dangler, Christopher, Kohn, Scott I., Stewart, Sarah G., Kishiyama, Clay H., Hermann, Weston A., Kelty, Kurt R.
• Granted Patent: US 10,534,028 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• 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: G01R 31/52 Testing for short-circuits, leakage current or ground faults
• 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 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0016 using shunting, discharge or bypass circuits
• CPC Class Codes: H02J 7/0025 Sequential battery discharge in systems with a plurality of batteries
• CPC Class Codes: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/00302 Overcharge 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

Abstract

An apparatus and method for identifying a presence of a short circuit in a battery pack. A fault-detection apparatus for a charging system that rapidly charges a collection of interconnected lithium ion battery cells, the safety system includes a data-acquisition system for receiving a set of data parameters from the collection while the charging system is actively charging the collection; a monitoring system evaluating the set of data parameters to identify a set of anomalous conditions; and a controller comparing the set of anomalous conditions against a set of predetermined profiles indicative of an internal short in one or more cells of the collection, the controller establishing an internal-short state for the collection when the comparing has a predetermined relationship to the set of predetermined profiles.

Claims

1. A fault-detection apparatus for a charging system that charges a collection of interconnected battery cells, the apparatus comprising:

a) a data-acquisition system for receiving a set of data parameters from the collection while the charging system is actively charging the collection, the set of data parameters measured during a charge cycle that begins with V<

V_max and deltaT<

(deltaT)_max, wherein deltaT is a maximum difference in temperature between the cells throughout the collection and an ambient temperature, wherein (deltaT)_max is a maximum acceptable difference in temperature that affects a change in voltage or current during charging;

b) a monitoring system evaluating said set of data parameters to identify a set of anomalous conditions; and

c) a controller comparing said set of anomalous conditions against a set of predetermined profiles indicative of an internal short in one or more cells of the collection, said controller establishing an internal-short state for the collection when said comparing has a predetermined relationship to said set of predetermined profiles.