Battery over temp explosive study

Author: Geoffrey Burke

Date: March 3, 2004

  1. Introduction
  2. File Information
  3. Materials
  4. Load Information
  5. Study Property
  6. Stress Results
  7. Deformation Results
  8. Design Check Results
  9. Conclusion
  10. Appendix

Flashlight Assembly Battery explosive animation Study


1. Introduction



18 Volt 10 amp Battery over temp from dead short resulting in explosive eruption


2. File Information



Flashlight Assembly Model eDrawing: Flashlight Assembly
Model name: Battery
Deformation Model eDrawing Battery Deformation
FOS Model eDrawing Battery Failure Analysis
Stress Study eDrawing COSMOSXpressStudy

eDrawing Plugin

3. Materials



No. Part Name Material Mass Volume
1 Battery 1345 Alloy 1.25242 kg 0.00046386 m^3



4. Load Information



Restraint
Restraint1 <Battery> on 9 Face(s) immovable (no translation).
Description:

Load
overheating <Battery> on 9 Face(s) with Pressure -2000 psi along direction normal to selected face
Description:


5. Study Property

Mesh Information
Mesh Type Solid mesh
Mesher Used: Standard
Automatic Transition: Off
Include Mesh Controls: Off
Smooth Surface: On
Jacobian Check: 4 Points
Element Size: 7.743 mm
Tolerance: 0.38715 mm
Quality: High
Number of elements: 10097
Number of nodes: 15268


Solver Information
Quality: High
Solver Type: FFE


6. Stress Results



Name Type Min Location Max Location
Plot1 VON: von Mises stress
21260.7 N/m^2
(-0.0198727 m,
0.11557 m,
-0.0133226 m)
1.32866e+008 N/m^2
(0.025231 m,
0.10287 m,
-0.0303862 m)



Battery-COSMOSXpressStudy-Stress-Plot1
JPEG
VIEW


7. Deformation Results



Plot No. Scale Factor
1 3577.4



Battery-COSMOSXpressStudy-Deformation-Plot2
JPEG
VIEW

8. Design Check Results



Battery-COSMOSXpressStudy-Design Check-Plot3
JPEG
VIEW


9. Conclusion

Prevent conductive materials direct contact across connection poles

10. Appendix

Material name: 1345 Alloy
Description:
Material Source Library files
Material Library Name Coswkmat.Lib
Material Model Type Linear Elastic Isotropic
Unit system: SI

Property Name Value
Elastic modulus 6.9e+010 N/m^2
Poisson's ratio 0.33
Yield strength 2.7574e+007 N/m^2
Mass density 2700 kg/m^3

Note:

COSMOSXpress design analysis results are based on linear static analysis and the material is assumed isotropic. Linear static analysis assumes that: 1) the material behavior is linear complying with Hooke’s law, 2) induced displacements are adequately small to ignore changes in stiffness due to loading, and 3) loads are applied slowly in order to ignore dynamic effects.

Do not base your design decisions solely on the data presented in this report. Use this information in conjunction with experimental data and practical experience. Field testing is mandatory to validate your final design. COSMOSXpress helps you reduce your time-to-market by reducing but not eliminating field tests.