Bus-bar Welding Guide
NESSCAP® Large Cylindrical Series Cell
Part Numbers
 ESHSR-0650C0-002R7A5
 ESHSR-1200C0-002R7A5
 ESHSR-1600C0-002R7A5
 ESHSR-2000C0-002R7A5
 ESHSR-3000C0-002R7A5
Bus-bar Welding Guide – Large Cylindrical Cell – Doc No. CD-523-010 rev.0
© 2010 NESSCAP Co., Ltd.
page 1
1. Introduction
This document is intended to provide technical guidelines for welding NESSCAP®
Large Cylindrical ultracapacitor cells with bus-bars. This guide will provide
general information related to laser welding of the bus-bar to the cell terminal and
will also recommend a material for the bus-bar.
2. Cell Information
Fig. 1. Cell dimensions and material.
Note: both terminals are aluminum
Bus-bar Welding Guide – Large Cylindrical Cell – Doc No. CD-523-010 rev.0
© 2010 NESSCAP Co., Ltd.
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3. Recommendation for Bus-bar
The recommended specifications for the bus-bars are listed in Table 1. While it is
possible to use different aluminum materials such as ASTM 4047, Nesscap
recommends the use of ASTM 3003 which is the material from which the
terminals are made.
Table 1. Recommend Bus-bar Specifications
Items
Recommendation spec.
Remarks
Material
ASTM 3003
(ISO AlMn1Cu,
DIN AlMnCu)
Same material as the cell
terminals
Thickness
2.9~3.2 mm
Cell terminals height are
2.875~3.125mm
Width
20~28 mm
Anode hole
diameter
Cathode hole
diameter
14.9~15.0 mm
14.0~14.1 mm
Cell anode terminal dia. is
14.85~14.9 mm
Cell cathode terminal dia. is
13.95~14.0 mm
An example of a bus-bar is provided in Figure 2. In this example, the pitch of the
cells is 63mm. Since the outer diameter of the cells is 60mm, the space in
between the cells is 3mm.
Fig. 2. Example of a Bus bar design
Bus-bar Welding Guide – Large Cylindrical Cell – Doc No. CD-523-010 rev.0
© 2010 NESSCAP Co., Ltd.
page 3
4. Welding
As long as there are no thermal or mechanical damage to the cells, any type of
welding machine can be used to connect the bus-bar to the cells. If laser welding
is being considered, Nesscap recommends the ND-Yag type laser welding
machine.
Since there are numerous makers and models of ND-Yag type laser welding
machine, it is difficult to provide a welding condition that can be applicable to all of
the machines. Therefore, this guide is intended to provide recommendations on
the shared parameters among most of the ND-Yag laser welding machines.
4-1. Preparing
In preparation for welding, the bus-bars and the cell terminals should be wiped
clean using alcohol and cloth.
4-2. Assembling
Assemble the bus-bar on the terminal taking caution not to damage the terminal
or the bus-bar.
4-3. Welding
(1)
(2)
(3)
(4)
(5)
(6)
(7)
Machine of capacity : ND-Yag type, 500W
Fiber : SI 800
Diameter of fiber : 0.8mm
Energy per pulse : 37~43 Joule/pulse
Pitch of pulse : 0.4~0.6mm
Diameter of pulse(bead size) : about 1.8mm
Welding depth : 0.8~1.4mm
Bus-bar Welding Guide – Large Cylindrical Cell – Doc No. CD-523-010 rev.0
© 2010 NESSCAP Co., Ltd.
page 4
Fig. 3. Pitch of pulse
Fig. 4. Welding depth (shown after tear test)
Bus-bar Welding Guide – Large Cylindrical Cell – Doc No. CD-523-010 rev.0
© 2010 NESSCAP Co., Ltd.
page 5
4-4. Example of a laser welding run
(1) Laser welding machine : ND-Yag type, 500W
(2) Material : ASTM 3003 terminal & ASTM 3003 bus-bar
(3) Frequency of pulse : 9Hz (9 pulses per second)
(4) Width of pulse : 8ms
(5) Energy per pulse : 39J
(6) Average of power : 351W
(7) Welding speed : 5mm/s (pitch of bead; 0.55mm)
Power (W)
39J
39J
39J
39J
39J
39J
39J
39J
39J
39J
Time (ms)
500ms
1000ms
8ms(width of pulse)
Fig. 5. Shape of pulses
Bus-bar Welding Guide – Large Cylindrical Cell – Doc No. CD-523-010 rev.0
© 2010 NESSCAP Co., Ltd.
page 6
Contact information
Website www.nesscap.com
Nesscap Co., Ltd.
(446-901) 750-8 Gomae-dong, Giheung-gu,
Yongin-si, Gyeonggi-do, Korea
Phone +82 31 289 0721
Fax +82 31 286 6767
Bus-bar Welding Guide – Large Cylindrical Cell – Doc No. CD-523-010 rev.0
© 2010 NESSCAP Co., Ltd.
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