Environmental Engineering Reference
In-Depth Information
Table 4.20 Ultra-capacitor technical specifications
Source
VC
(F)
R
(m
W
)
E
(Wh/kg)
P
(W/kg)
at 95%
efficiency
Mass
(kg)
P
/
E
Skeltech
(cell only)
2.3
615
0.50
3.9
3,500
0.085
897
Saft
2.7
3,500
1
4.1
336
0.65
82
Maxwell-Montena
2.5
2,700
0.32
2.55
784
0.70
307
Ness
2.7
4,615
0.28
3.70
846
0.86
228
Panasonic
2.5
2,500
0.43
3.7
1,035
0.39
280
Okamura/Honda
2.7
1,350
1.5
4.9
650
0.21
133
Electronic
concepts*
2.3
2,000
3
3.1
178
0.47
57
ESMA
1.3
10,000
0.275
1.1
156
0.55
142
*
Estimated from constant current discharge testing. Specific power is taken at 95% efficiency.
Source
: From Table 2 in Reference 36, modified.
2.5
V
o
= 2.3
V
V
c
=
V
o
-
R
i
I
2.0
I
= 10 A constant current discharge
1.5
V
1.0
W
e
= 0.5
V
o
IT
f
T
f
= 460 s
0.5
0.0
-50
0
50
100
150
200
250
300
350
400
450
500
Time (s)
Figure 4.41 Ultra-capacitor constant current discharge testing
The accumulated energy in the ultra-capacitor is determined by integrating the
discharge voltage curve over the full discharge time:
I
t
T
f
V
ð
t
Þ¼
V
c
1
T
f
ð
Idt
t
T
f
W
e
¼
V
c
1
ð
4
:
29
Þ
0
IT
f
V
c
C
¼
V
o
V
c
I
R
i
¼
