Ex Parte Zhang et al

Patent Trial and Appeal Board

May 1, 2017

13023748 (P.T.A.B. May. 1, 2017)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O.Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/023,748 02/09/2011 Yilu Zhang P012540-RD-MJL 9319
72823 7590
Quinn IP Law
21500 Haggerty Road
Suite 300
Northville, MI 48167
05/03/2017 EXAMINER
TRISCHLER, JOHN T
ART UNIT PAPER NUMBER
2859
NOTIFICATION DATE DELIVERY MODE
05/03/2017 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
amb@quinnlawgroup.com
U S Docketing @ quinnlawgroup.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte YILU ZHANG, NIANNIAN TONG, MUTASIM A. SALMAN,
KEVIN R. BAINBRIDGE, and DAVID W. WALTERS
Appeal 2016-001880
Application 13/023,748
Technology Center 2800
Before JAMES C. HOUSEL, GEORGE C. BEST, and JEFFREY R. SNAY,
Administrative Patent Judges.
SNAY, Administrative Patent Judge.
DECISION ON APPEAL1
Appellants2 appeal under 35 U.S.C. § 134(a) from the Examiner’s
decision rejecting claims 1—20. We have jurisdiction under 35 U.S.C.
§ 6(b). We REVERSE.
1 We refer to the Specification (“Spec.”) filed February 9, 2011, amended
August 14, 2013; Final Office Action (“Final Act.”) dated March 27, 2015;
Appellants’ Appeal Brief (“App. Br.”) dated July 30, 2015; Examiner’s
Answer (“Ans.”) dated October 14, 2015; and Appellants’ Reply Brief
(“Reply Br.”) dated November 23, 2015.
2 Appellants identify GM Global Technology Operations, LLC, as the real
party in interest. App. Br. 2.
Appeal 2016-001880
Application 13/023,748
BACKGROUND
The subject matter on appeal regards methods for determining a
battery’s state-of-charge (“SOC”) based on an open circuit voltage (“OCV”)
which is estimated from voltage and temperature measurements obtained at
different times prior to equilibrium in a non-charging state. Spec. 14.
Claims 1 and 13—the only independent claims on appeal—are reproduced
from the Claims Appendix of the Appeal Brief:
1. A method of determining a state-of-charge of a battery
for a vehicle, the vehicle being in a charging state when the
engine is operating and a non-charging state when the engine is
not operating, the method comprising the steps of:
measuring a first battery voltage at a first predetermined
time after battery charging is discontinued in the non-charging
state;
measuring a first temperature of the battery coinciding
with the first battery voltage;
measuring a second battery voltage at a second
predetermined time after the first predetermined time with the
vehicle in the non-charging state, the second predetermined
time being greater than the first predetermined time;
measuring a second temperature of the battery coinciding
with the second battery voltage;
calculating an average temperature based on the first
temperature measurement and the second temperature
measurement;
determining a fixed time constant based on the average
temperature;
estimating an open circuit voltage as a function of the
first voltage measurement, the second voltage measurement,
and the fixed time constant; and
determining a state-of-charge of the battery based on the
estimated open circuit voltage.
13. A system for determining a state-of-charge of a battery
for a vehicle, the vehicle being in a charging state when the
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Appeal 2016-001880
Application 13/023,748
engine is operating and a non-charging state when the engine is
not operating, the system comprising:
a battery;
a voltmeter for measuring a first battery voltage at a first
predetermined time after battery charging is discontinued in the
non-charging state, and for measuring a second battery voltage
at a second predetermined time after battery charging is
discontinued, the second predetermined time being greater than
the first predetermined time;
a temperature sensor for measuring a first temperature of
the battery coinciding with the first battery voltage, and for
measuring a second temperature of the battery coinciding with
the second battery voltage; and
a control module for determining a fixed time constant as
a function of the first and second temperature measurements,
the control module estimating an open circuit voltage at
equilibrium as a function of the first battery voltage, the second
battery voltage, and the fixed time constant, wherein the control
module determines a state-of-charge of the battery based on the
estimated open circuit voltage.
REJECTIONS3
I. Claims 1, 2, 5—16, and 18—20 stand rejected under 35 U.S.C. § 103(a)
as unpatentable over Zhang4 and Wortham.5
II. Claims 3, 4, and 17 stand rejected under 35 U.S.C. § 103(a) as
unpatentable over Zhang, Wortham, and Iwane.6
3 Final Act. 3—22; Ans. 2. The Examiner rejects claims 4, 7, 8, 10—12, 14,
15, and 18—20 in the Final Office Action but, without explanation, omits
these claims from those identified in the Answer as subject to rejection on
Appeal. Compare Final Act. || 6, 24, with Ans. 2. Because we reverse the
Examiner’s rejections as to all claims, the above-noted inconsistency is
without consequence.
4 US 2009/0157335 Al, published June 18, 2009 (“Zhang”).
5 US 8,203,305 Bl, issued June 19, 2012 (“Wortham”).
6 US 7,899,631 B2, issued March 1, 2011 (“Iwane”).
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Appeal 2016-001880
Application 13/023,748
DISCUSSION
A dispositive issue in this appeal is whether the Examiner’s finding
that Wortham teaches estimating an open circuit voltage as a function of first
and second voltage measurements and a temperature dependent fixed time
constant constitutes reversible error.7 Particularly, the Examiner finds that
Zhang “does not disclose . . . estimating an open circuit voltage as a function
of the first voltage measurement, the second voltage measurement, and the
fixed time constant.” Final Act. 4. Rather, Zhang discloses periodically
measuring a battery’s open circuit voltage via a voltage sensor, so that a
change in the battery’s state of charge over time may be determined and
correlated to the battery’s parasitic load. Zhang Abstract, || 4, 12, 14.
Accordingly, the Examiner’s obviousness determination in Rejections I and
II is premised on the finding that Wortham teaches estimating a battery’s
open circuit voltage from voltage and temperature measurements taken at
different times. For the reasons stated in the Appeal Brief and below, we
agree with Appellants that the Examiner’s finding as to Wortham is not
supported.
Like Zhang, Wortham discloses determining open circuit voltage at a
given point in time by measuring battery terminal voltage. Wortham col. 7,
11. 23—26 (“The battery terminal voltage is monitored and converted to
digital form by the ADC. That value is effectively input into a digital filter,
7 Compare Final Act. 4 (“Wortham does teach . . . estimating an open
circuit voltage (col. 10 lines 26 — 30) as a function of the first voltage
measurement, the second voltage measurement, and the fixed time constant
(col. 6 lines 63 — 66)”), with App. Br. 9 (“The limitation of an open circuit
voltage determined as a function of the first voltage measurement, the
second voltage measurement, and the fixed time constant is neither
described nor suggested as alleged.”).
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Appeal 2016-001880
Application 13/023,748
the output of which is the open circuit voltage OCV.”); see also id. col. 3,11.
41—46. The Examiner cites column 6, lines 63—66, and column 10, lines 26—
30 of Wortham. Final Act. 4. At the cited portion of column 6, Wortham
states that a fixed time-constant may be used in connection with modeling
capacitance over time. At the cited portion of column 10, Wortham provides
a mathematical relationship involving open cell voltage and a single voltage
value, “Veen”, where Vceii represents the battery’s terminal voltage. See
Wortham col. 8,11. 49—50 (“Vceii is the terminal voltage on the cell.”).
Nowhere in the cited portions of Wortham do we find evidence
sufficient to support the Examiner’s finding that Wortham teaches
estimating a battery’s open circuit voltage from voltage and temperature
measurements taken at different times. As such, the Examiner has not set
forth a factual basis sufficient to support a prima facie case of obviousness.
For that reason, we cannot sustain the Examiner’s rejections.
DECISION
The Examiner’s decision rejecting claims 1—20 is reversed.
REVERSED
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