0
Research Papers

Dynamic Stress Analysis of Battery Tabs Under Ultrasonic Welding

[+] Author and Article Information
Bongsu Kang

Engineering Department,
Indiana University–Purdue
University Fort Wayne,
Fort Wayne, IN 46805
e-mail: kang@engr.ipfw.edu

Wayne Cai

Advanced Propulsion Manufacturing
Research Group,
Manufacturing Systems Research Lab,
General Motors Global R&D Center,
Warren, MI 48090
e-mail: wayne.cai@gm.com

Chin-An Tan

Mechanical Engineering Department,
Wayne State University,
Detroit, MI 48202
e-mail: tan@wayne.edu

Low-cycle fatigue fracture is associated with fatigue that occurs at lower than about 104 to 105 cycles [24].

When higher order beam models such as the Timoshenko beam model that includes the effects of rotary inertia and shear deformation are used, the frequencies can be slightly different. The Timoshenko beam model is typically used for a beam whose slenderness ratio is less than 10.

1Corresponding author.

Contributed by the Manufacturing Engineering Division of ASME for publication in the JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING. Manuscript received September 12, 2013; final manuscript received February 19, 2014; published online May 21, 2014. Assoc. Editor: Tony Schmitz.

J. Manuf. Sci. Eng 136(4), 041011 (May 21, 2014) (8 pages) Paper No: MANU-13-1341; doi: 10.1115/1.4026990 History: Received September 12, 2013; Revised February 19, 2014

Ultrasonic metal welding is widely used for joining multiple layers of dissimilar metals, such as aluminum/copper battery tabs welding onto copper busbars. It is therefore important to have a robust product/process design using ultrasonic metal welding that ensures consistent welds with desired quality. In this work, the effects of longitudinal and flexural vibrations of the battery tab during ultrasonic welding on the development of axial normal stresses that occasionally cause cracks near the weld area are studied by applying a one-dimensional continuous vibration model for the battery tab. Analysis results indicate that fracture could occur near the weld area, due to low cycle fatigue as a result of large dynamic stresses induced by resonant flexural vibration of the battery tab during welding. This study provides a fundamental understanding of battery tab dynamics during ultrasonic welding and its effects on weld quality, and can be used to develop guidelines for product/process design of ultrasonically welded battery tabs.

FIGURES IN THIS ARTICLE
<>
Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 3

Thin beam with coordinate x and transverse displacement w

Grahic Jump Location
Fig. 2

Thin beam with coordinate x and longitudinal displacement u

Grahic Jump Location
Fig. 1

Schematics of the weld unit and ultrasonic welding setup

Grahic Jump Location
Fig. 4

Flexural natural frequency loci of the thin beam (d=45 mm and h=0.2 mm) as a function beam length L for (a) aluminum and (b) copper. The solid (——) and dashed (- - - -) curves represent the clamped-free (c–f) and clamped-clamped (c–c) case, respectively. Notations for the markers are, for example, 4 c–f denotes the 4 th vibration mode for the clamped-free beam

Grahic Jump Location
Fig. 8

σ0 of the unconstrained tab as a function of tab length L for (a) aluminum tab and (b) copper tab when Ω = 20 kHz

Grahic Jump Location
Fig. 5

A schematics of the battery cell assembly (with the cell pouch partially shown) under ultrasonic welding

Grahic Jump Location
Fig. 6

A schematics of tab and its boundary conditions with equivalent mass and stiffness

Grahic Jump Location
Fig. 7

Axial stress distribution along the aluminum unconstrained tab when Ω = 20 kHz and L = 17 mm for the (a) free boundary and (b) clamped boundary at x = L

Grahic Jump Location
Fig. 9

σ0 of the cell-integrated aluminum tab as a function of tab length L. (a) Effect of kf when mf = 0, (b) effect of mf when kf = 0, (c) effect of mf when kf = 25 kN, and (d) effect of mf when kf = 50 kN

Grahic Jump Location
Fig. 10

σ0 of the cell-integrated copper tab as a function of tab length L. (a) Effect of kf when mf = 0 and (b) effect of mf when kf = 0

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In