Ex Parte Nemoto et al

Board of Patent Appeals and Interferences

Aug 27, 2007

09997604 (B.P.A.I. Aug. 27, 2007)

The opinion in support of the decision being entered today is
not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte HIROSHI NEMOTO and KENSHIN KITOH
____________

Appeal 2007-3662
Application 09/997,604
Technology Center 1700
____________

Decided: August 27, 2007
____________

Before CHARLES F. WARREN, PETER F. KRATZ, and CATHERINE Q.
TIMM, Administrative Patent Judges.

TIMM, Administrative Patent Judge.

DECISION ON APPEAL
Appellants appeal under 35 U.S.C. § 134(a) from the Examiner’s
decision rejecting claims 11-14, 16-21, 23, and 24. We have jurisdiction
under 35 U.S.C. § 6(b).
We AFFIRM.

Appeal 2007- 3662
Application 09/997,604

I. BACKGROUND
The invention relates to the production of lithium secondary batteries.
Claim 17 is illustrative of the subject matter on appeal:
17. A method of making a lithium secondary battery having low
internal resistance, comprising:

welding a plurality of current collecting portions directly to a positive
electrode, said positive electrode comprising a positive electrode active
material formed by a process comprising:

forming a raw material mixture comprising positive
electrode precursor material, said raw material mixture
comprising Li and Mn; and

heating said raw material mixture to a temperature and
for a time which is effective to convert said raw material
mixture into a positive electrode active material having a cubic
spinel structure, primary particles of the positive electrode
active material having a substantially octahedral shape
constituted mainly by flat crystal faces, said primary particles
including particles having at least one side of each flat crystal
face of length of 1 µm or more;

said battery having a capacity of 2 Ah or more.

The Examiner relies on the following prior art references to show
unpatentability:
Okada1 JP 08-217452 Aug. 27, 1996
Zhong US 5,700,597 Dec. 23, 1997
Watanabe US 6,106,975 Aug. 22, 2000
Zhong US 5,631,104 May 20, 1997
Manev US 5,961,949 Oct. 5, 1999

1 With regard to Okada, we have considered both the machine translation
and the translation provided by Schreiber Translations, Inc. We cite to the
Schreiber translation in the following discussion.
2
Appeal 2007- 3662
Application 09/997,604

Idota US 5,686,203 Nov. 11, 1997

The Examiner maintains the following rejections: 2
1. Claims 11-14, 16-21, and 23 under 35 U.S.C. § 103(a) as
unpatentable over:
a. Okada in view of Zhong ‘597 and Watanabe;
b. Zhong ‘104 in view of Zhong ‘597 and Watanabe; and
c. Manev in view of Zhong ‘597 and Watanabe.
2. Claim 24 under 35 U.S.C. § 103(a) over the prior art of rejections
1b and 1c above, each further in view of Idota.
3. Claims 11-14, 16-21, 23, and 24 under 35 U.S.C. § 112, ¶ 1 as
lacking enablement for the full scope of the claims.

II. DISCUSSION
Obviousness
With regard to all the obviousness rejections, the main issue on appeal
arising from the contentions of Appellants and the Examiner is: Do any one
of Okada, Zhong ‘104, or Manev teach or suggest primary particles “having
a substantially octahedral shape” and “including particles having at least one
side of each flat crystal face of length of 1 µm or more?”
For the reasons that follow, we answer in the affirmative.
With regard to the question at hand, Appellants do not argue any
claim apart from the others. We select claim 17 to represent the claims on
appeal in deciding the issue. Claim 17 requires heating to form “positive

2 The Examiner has withdrawn a rejection of claims 12 and 19 under 35
U.S.C. § 112, ¶ 1 (Answer 2).
3
Appeal 2007- 3662
Application 09/997,604

electrode active material having a cubic spinel structure, primary particles of
the positive electrode active material having a substantially octahedral shape
constituted mainly by flat crystal faces.” (Emphasis added.) While we have
considered each rejection individually, as the issue is the same in each, we
discuss them together.
We consider first the scope of the language of the claims. We do so
with the understanding that during examination, “claims . . . are to be given
their broadest reasonable interpretation consistent with the specification, and
. . . claim language should be read in light of the specification as it would be
interpreted by one of ordinary skill in the art.” In re Am. Acad. of Sci. Tech.
Ctr., 367 F.3d 1359, 1364, 70 USPQ2d 1827, 1830 (Fed. Cir. 2004).
According to the Specification:
In the positive electrode active material having such a
composition [, i.e., lithium manganese oxide composed mainly
of Li and Mn,] and a cubic spinel structure, the primary
particles mostly have a substantially octahedral shape
constituted mainly by flat crystal faces, as seen in Fig. 1 which
is a SEM photograph showing a morphology of such primary
particles. That is, flat crystal faces intersect with each other at
the surface of each primary particle to form clear edge lines,
and each primary particle has a shape close to the octahedron of
cubic spinel structure.
The primary particles seen in Fig. 1 also include particles
of other shapes, that is, (a) particles wherein the apex formed by
intersection of four crystal faces of octahedron is not complete
and is formed in the form of a plane or an edge, (b) particles
wherein a different crystal face is formed at the edge formed by
intersection of two crystal faces of octahedron, and (c) particles
wherein one crystal face is jointly owned by two primary
particles or wherein other primary particle grows from the
surface of one primary particle. These primary particles do not
have a completely octahedral shape but can be regarded as a
substantially octahedral shape. In the present invention, the
4
Appeal 2007- 3662
Application 09/997,604

“substantially octahedral shape” include these various shapes
and further include those polyhedrons formed by partial
chipping of the above shapes or by joint possession of crystal
face in complicated manner between two primary particles.
The positive electrode active material used in the present
lithium secondary battery is characterized by consisting of
primary particles mostly having the above-mentioned
morphology. Thus, all the primary particles need not have a
substantially octahedral shape.

(Specification 7:24 to 8:24).
As the Specification makes clear, Appellants intend “substantially
octahedral shape” to include crystal shapes that have some aspect of
octahedral configuration but are not completely octahedral in nature. For
instance, even if a crystal has a different crystal face where two faces of an
octahedron would normally form an edge, or if a crystal is a complicated
polyhedron based on the growth of one primary particle from the surface of
another, it will still be “substantially octahedral” as that terminology is used
in the claims.
Turning to the phrase “said primary particles including particles
having at least one side of each flat crystal face of length of 1 µm or more,”
we note the word “including” in the phrase. Any primary particles including
even a small amount of particles big enough to meet the 1 µm or more face
size, will meet the requirements of claim 17.
Turning to the prior art and considering what it teaches in comparison
to what is encompassed by claim 17, we determine that the references
applied by the Examiner teach or suggest heating to form primary particles
of crystallinity and size within the claimed ranges.
5
Appeal 2007- 3662
Application 09/997,604

Okada, Zhong ‘104, and Manev are, like Appellants, directed to
forming positive electrode active material from lithium manganese oxides
and metal substituted lithium manganese oxides. Each reference discloses
that the compounds have a spinel or spinel-like crystal structure (Okada ¶
0036; Zhong ‘104, col. 5, ll. 12-23; Manev, col. 1, ll. 16-19). Appellants’
Specification and Okada reflect the understood meaning of “spinel” as a
class of minerals that form octahedral crystals.3 (Specification 7:24 to 8:6
“shape close to the octahedron of cubic spinel structure”; Okada, ¶ 0036
describing the spinel structure in terms of its octahedral packing structure.)
Appellants contend that Okada is directed to particles of needle-like
(acicular) shape. But the only reference to such a shape is in paragraph 0107
of Okada. Paragraph 0107 is directed to a comparative example and states
that what was obtained in that example was a compound “of acicular regular
octahedron particles with a one side length of 1 µm or greater.” It is
“comparative” because its BET specific surface was outside the desired
range.

3See McGraw-Hill Dictionary of Scientific and Technical Terms (5th ed.
1994) defining “spinel” as “1. MgAl2O4 A colorless, purplish-red,
greenish, yellow, or black mineral, usually forming octahedral crystals,
and characterized by great hardness; used as a gemstone. 2. A group of
minerals of general formula AB2O4, where A is magnesium, ferrous iron,
zinc, or manganese, or a combination of them, and B is aluminum, ferric
iron, or chromium.” See also Dictionary.com (v 1.1): “1. any of a group
of minerals composed principally of oxides of magnesium, aluminum,
iron, manganese, chromium, etc., characterized by their hardness and
octahedral crystals. 2. a mineral of this group, essentially magnesium
aluminate, MgAl2O4, some varieties being used as gems.”
6
Appeal 2007- 3662
Application 09/997,604

We cannot agree that Okada is only teaching the formation of acicular
regular octahedron particles. That language is not used to describe any of
the other exemplified compounds.
Nor can we agree that Appellants’ claims exclude particles of
“acicular regular octahedron” shape. Figure 4 of Okada shows the primary
particles of comparative example 1, and that figure shows particles of
“substantially octahedral shape” within the meaning of the claims. While
some of the particles, as argued by Appellants, include flat faces where
edges would arise in an ideal octahedron, as discussed above, the claim
language “substantially octahedral shape” allows for such deviations in
shape (Specification 8:10-12). The “substantially” language also
encompasses polyhedrons based on the growth of one primary particle from
the surface of another primary particle, shapes also seen in Figure 4 (see also
Appellants’ Appendices E and F).
With regard to the length of the crystal face, Okada describes the
particles of comparative example 1 as having faces of the claimed length
(Okada ¶ 0107). Moreover, given the diameters of the particles of the other
examples (10 µm or smaller (Exs. 4 and 5); 5 µm or smaller (Exs. 1-3)), they
too would have at least some faces of 1 µm or more. For an octahedral
polygon, the length of a face has to be more than half the diameter of the
particles. Moreover, as we explained above, to meet the claim only a small
amount of the faces need meet the 1 µm or more length limitation.
Furthermore, Manev provides evidence that optimizing the particle
size and thus the face length through routine experimentation would have
also been obvious to one of ordinary skill in the art. Manev explains that the
mean particle size and the particle size distribution directly influence the
7
Appeal 2007- 3662
Application 09/997,604

properties of the positive electrode of the secondary lithium batteries
(Manev, col. 1, ll. 40-47). Manev discusses the properties affected by the
mean particle size (Manev, col. 1, ll. 43 to col. 2, l. 10), and provides
guidance as to how to obtain desired particle size by selecting appropriate
heating temperatures, heating duration, and the size of manganese compound
starting particles (Manev, col. 4, l. 30 to col. 5, l. 33). Manev discloses that
a mean particle size of 10-15 µm provides good properties (Manev, col. 5, ll.
24-33). Particles of such size necessarily have faces with lengths of 1 µm or
more.
Okada, Zhong ‘104, and Manev each describe how to obtain spinel
crystals by heating, in one or two stages, a mixture of salts and oxides of Li,
Mn, and any other metal to be included in an oxidizing atmosphere (Okada
¶¶ 0075 and 78 (heat to 500°C or lower then heat to 500-850°C, for,
preferably, 10 or more hours); Zhong ‘104, col. 6, ll. 3-6 (750-950°C one or
more times); Manev, col. 4, ll. 30-54 (400-600°C for at least 12 hours then
700-900°C for at least 10 hours). The temperatures and times of the prior art
are in substantially the same range as Appellants’ temperatures and times
(Specification 11:5-10 (700-900°C for 5-50 hours)). But most importantly,
all the references perform the heating step specifically to obtain a spinel
structure, i.e., crystals of octahedral shape. One of ordinary skill in the art
would have conducted the process in order to get the desired crystals.
We also agree with the Examiner that it is reasonable to conclude that
the primary particles formed in the Inventive Example 3 of Zhong ‘104 (col.
9, ll. 32-37) would have particles with face lengths of 1 µm or more as
claimed. While Appellants contend that not all temperatures and times will
result in the claimed morphology (Br. 14-15), Inventive Example 3 of Zhong
8
Appeal 2007- 3662
Application 09/997,604

‘104 describes a very specific heating regime for a specific composition.
Zhong ‘104 further specifically desires to obtain spinel crystalline structure
and optimizes the particles for use in lithium batteries. Based on the
similarities of the composition and heating regime as well as the crystalline
structure, it is reasonable to shift the burden to Appellants to show that there
is, in fact, a difference between the particles of Example 3 of Zhong ‘104
and those claimed. Appellants have not presented convincing evidence of a
patentable difference.
We determine that each one of Okada, Zhong ‘104, and Manev teach
or suggest primary particles “having a substantially octahedral shape” and
“including particles having at least one side of each flat crystal face of length
of 1 µm or more” as required by the claims.
With regard to the combination of Okada, Zhong ‘104, and Manev,
respectively with Zhong ‘597 and Watanabe, Appellants make generalized
statements about differences between what the references teach and what is
claimed (Br. 16-17, Br. 20-21, Br. 23-24), but Appellants do not identify any
specific reversible error in the Examiner’s rejections. There is, therefore, no
further issue in this regard for us to consider.
With respect to the rejection of claim 24, Appellants present no
further arguments specific to the limitation for which Idota was added as
evidence of obviousness. Again, there is no further issue for us to consider.
Enablement
Given the level of guidance in the Specification and in the prior art
concerning how to obtain primary particles of spinel crystallinity, i.e.,
crystals of substantially octahedral shape, and how to control particle size,
we cannot agree with the Examiner that Appellants need limit their claims to
9
Appeal 2007- 3662
Application 09/997,604

the metal substituted lithium manganese oxide Appellants exemplify in the
Specification. The evidence tends to show that no more than routine
experimentation was required of one of ordinary skill in the art of lithium
secondary battery production, and the Examiner has not sufficiently rebutted
that evidence.

III. CONCLUSION
We sustain the rejection of claims 11-14, 16-21, 23, and 24 under 35
U.S.C. § 103(a), but we do not sustain the rejection of claims 11-14, 16-21,
23, and 24 under 35 U.S.C. § 112, ¶ 1.

IV. DECISION
The decision of the Examiner is affirmed.

V. TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal maybe extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED

10
Appeal 2007- 3662
Application 09/997,604

tc/ls

BURR & BROWN
P.O. BOX 7068
SYRACUSE, NY 13261-7068

11