Mobile Energy Company.
Akio FurukawaManagerNi Battery System Section No.2Technical service departmentAlkaline Technology Business UnitMobile Energy CompanyComponents Business GroupSanyo Electric Co., Ltd.
Development of
Dry Cell Replaceable Ni-MH Batteries
Mobile Energy Company.
1300mAh
1450mAh
1600mAh
1700mAh
1850mAh
2100mAh
2300mAh
11% UP
10% UP
6% UP
9% UP
14% UP
10% UP
Sanyo Electric Co., Ltd.
The capacity of AA size Ni-MH batteries
has been increased remarkably.
Improvement of the active material is necessary
to increase the capacity furthermore.
Further increase of capacity requires
a breakthrough technology
History of AA size Dry Cell Replaceable
Ni-MH Batteries
Mobile Energy Company.
Development of a new alloy with higher capacity and better corrosion resistance than the current alloy (AB5type) as the key active material of the negative electrode.
Development of higher capacity Ni-MH battery with the new alloy.
Purpose
Method
Optimization of the composition of the new alloy (Super-
lattice alloy) to improve corrosion resistance.
Mobile Energy Company.
AB5 alloy (Mm-Ni-Co-Mn-Al)
0.70.32.8Co0.5
Cycle condition:1It=1000mACharge:1It , V(10mV)Discharge:1It , E.V=1.0VRoom temperature
0.70.33.3
Cap
acit
y (
% v
s. in
itia
l)
40
50
60
70
80
90
100
110
0 100 200 300 400 500 600
Cycle Number
The charge and discharge cycle characteristics
Mobile Energy Company.
Test conditionCharge:150mA/g x2hr50minDischarge:150mA/g, E.V.= 0.7V
-MH
ele
ctr
od
e p
ote
nti
al
(V v
s.
Hg
O/H
g)
0.830.173.10.2
AB5 alloy(Mm-Ni-Co-Mn-Al)
0.6
0.7
0.8
0.9
1.0
0 100 200 300 400
Discharge capacity(mAh/g)
40
50
60
70
80
90
100
110
0 200 400 600 800 1000
Cycle Number
Mm0.83Mg0.17Ni3.1Al0.2
Cap
acit
y (
% v
s. in
itia
l)
Cycle condition:1It=1700mACharge:1It , V(10mV)Discharge:1It , E.V.=1.0VRoom temperature
AB5 alloy(Mm-Ni-Co-Mn-Al)
+10%
+30%
Comparison between the current AB5 type alloy
and the super-lattice alloy
Mobile Energy Company.
Discharge capacity (mAh)
Ce
ll V
olt
ag
e(V
)
0.80.9
11.11.21.31.41.51.61.71.8
0 500 1000 1500 2000 2500
Test Condition:
Charge: 250mA x 16hr at=25Discharge: 500mA, E.V.=1.0V
Ni-MH 2300
using AB5 alloy
Ni-MH 2500
using superlattice alloy
The cell capacity increase by using super-lattice alloy
Mobile Energy Company.
Sanyo HR-3U
(Typ. 2500mAh)
Brand A : AA
(Printed 2400mAh)
The capacity of HR-3U is the highest !!
The cycle life of HR-3U(Typ.2500mAh)
is the longest in the class.
Brand B : AA
(Printed 2500mAh)
Brand C : AA
(Printed 2300mAh)
Accelerated cycle test
Mobile Energy Company.
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
0 10 20 30 40 50 60 70 80 90
Charge & Discharge Time (min)
Cell
Voltage (
V)
1Cycle
2Cycles
3Cycles
4Cycles
5Cycles
Before Test
Cycle Condition :
Charge : 2500mA (-V=10mV)
Rest : 1h
Discharge : 2500mA (E.V.=1.0V)
Rest : 1h
Ambient Temp. : 20C
n=2
Storage Condition :
Ambient Temp. : 40C
Storage Term : 1Month
Cell is connected with Resistor.
(2ohm)
HR-3U(Typ.2500mAh) showed the best
recovery against Over-discharge !
Capacity loss is very small
Mobile Energy Company.
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
0 10 20 30 40 50 60 70 80 90Charge & Discharge Time (min)
Cell
Voltage (
V)
1Cycle
2Cycles
3Cycles
4Cycles
5Cycles
Before Test
Storage Condition :
Ambient Temp. : 40C
Storage Term : 1Month
Cell is connected with Resistor.
(2ohm)
Cycle Condition :
Charge : 2300mA (-dV=10mV)
Rest : 1h
Discharge : 2300mA (E.V.=0.8V)
Rest : 1h
Ambient Temp. : 20C
n=2
An Example
Recovery from over-discharge of Others AA; Big capacity loss!
Very big capacity loss
Mobile Energy Company.
Sanyo HR-3U
(Typ. 2500mAh)
Brand A : AA
(Printed 2400mAh)
At 40 deg.C
Brand B : AA
(Printed 2300mAh)
HR-3U(Typ.2500mAh) has the best
charge-retention (The slowest Self-discharge)
Brand C : AA
(Printed 2300mAh)
Mobile Energy Company.
0306090
120150
The Super-lattice hydrogen absorbing alloy (a breakthrough technology
in Ni-MH battery history since 1990) contributed the highest capacity
and best performance in AA size Dry Cell Replaceable Ni-MH Batteries.
AA : Typ. 2500mAh, AAA : Typ. 900mAh
The highest capacity in the world
with balanced performance.
High temp. Charge(40)
Recovery fromOver-discharge(60,14days)
Cell capacity
Low temp. discharge (0)
Self-discharge(40,14days)
High-rate discharge(3It)
Ni-MH 2500(Superlattice alloy)
Ni-MH 2300(AB5 alloy)
AA size Dry Cell Replaceable Ni-MH Battery
with Super-lattice hydrogen absorbing alloy
Mobile Energy Company.
1300mAh
1450mAh
1600mAh
1700mAh
1850mAh
2100mAh
2300mAh
2500mAh
11% UP
10% UP
6% UP
9% UP
14% UP
10% UP
9% UP
Sanyo Electric Co., Ltd.
History of AA size Dry Cell Replaceable
Ni-MH Batteries
Mobile Energy Company.
A new Super-lattice hydrogen absorbing alloy with higher
capacity and better corrosion resistance than the current alloy (AB5type) as the key active material of negative electrode of Ni-MH
battery was successfully developed.
The high capacity (2500mAh*) of AA size Dry Cell Replaceable Ni-
MH Battery was developed with the Super-lattice hydrogen
absorbing alloy and has been shipped since July 2004.
2500mAh* is still the highest capacity (among mass-produced AA
size Ni-MH batteries ) in the world at this moment (Feb. 20, 2005).
(*:The capacity is defined by IEC 61951-2)
Conclusion
