Members

Brian AlanoJae Shin Korkut OzuyenerChristopher SheltonMatt Zwiesler

Introduction Planning Design Specification Competitive Benchmark Concept Design Product Evaluation Impact Statement Conclusion Recommendation

462 Capstone design Design of battery enclosure for

Toyota Prius Used with existing Hybrid technology

to further improve car performance Plug-in technology used to double

overall vehicle performance

Schedule in Microsoft Excel Calendar in Yahoo! batterybox group Weekly team meetings Weekly and daily status reports

ME462 Project Plan

Assigned To

Man-Hours

hours complete

% complete Inputs Deliverables Deadline

Currently Projected Completion

Actual Completion

Specification Definition 0% approved PDP approved QFD 01-31 01-30

Jae 1 0 0%ME462 Project Handout who on QFD 01-24

Jae 4 0 0%

sponsor, ME462 Project Handout, who on QFD what on QFD 01-24

Weigh customer requirements Jae 0.5 0 0%

research, ME462 Project Handout, what on QFD what on QFD 01-24

Matt 12 0 0%research, what on QFD

Now v. What on QFD (benchmarks v. requirements) 01-27

Matt 6 0 0% now, what on QFDWhat v. how & how v. how on QFD 01-28

Matt 4 0 0% now, how on QFD

Now v. How on QFD (benchmarks v. specifications) 01-28

Set targets Jae 6 0 0%now, what, how on QFD

how v. how much and now v. how much on 01-29

QFD approval Team 5 0 0% QFD approved QFD 01-30

Task

Evaluate competition against cust. requirements

Evaluate competition against engr. specifications

Generate engineering specifications

Description of customers

Generate customers requirements

38.5

Maintenance cost ($/year) Total cost of prototype Trunk space after installation (sq. in) Number of battery modules that fit (#) Max internal temp at max power draw

(deg. C) Explosive force experienced without

fragmenting (kg TNT)

HymotionPros

CompactAppearance

ConsNo analysis

Stress & ThermalNo spare tire

solutionNo fans

Jerry’s BoxPros

Cheap Compact

ConsWeak MaterialNo Analysis

Stress & ThermalDangerousNo fan

Latch High Strength

MaterialSS + Rugged Alloy

Steel High Holding Capacity

7500 lbs Easy to use Simple design Adjustable

Constraints Interference check

with trunk interior

Potential energy contained by batteries equal to 25.2 MJ

Laws of thermodynamics- pressure that results from complete release of energy equal to 21.58 ksi 9.6” thick Al-7075T6 necessary

BlastWrap data indicates it can absorb 4.9 MJ Leaves energy that could result in pressure of

17.38 ksi 8.4” thick Al-7075T6 necessary

This is worst case scenario, and disregards any ventilation also

Rectangular pressure vessel calculations from ASME Boiler and Pressure Codes

1/4” thick Al-7075T6 can handle 22.17 psi.

This equals about 25.82 kJ. Added to energy absorbed by BlastWrap

results in total energy designed enclosure can handle= 4.9258 MJ

Thickness (in) Pressure (psi)

Alum 2014T6 Alum 2024T3 Alum 7075T6

0.01 0.033554634 0.030199171 0.035951394

0.1 3.338898164 3.005008347 3.57739089

0.2 13.28273245 11.9544592 14.23149905

0.25  20.69781195 18.62803075 22.17622708

0.3 29.72399151 26.75159236 31.84713376

0.4 52.55748475 47.30173627 56.3115908

0.5 81.68028005 73.51225204 87.51458576

Hand calculated allowable pressure used

Bottom of enclosure used as it would experience largest moments

Symmetry- Forces applied to two sides

Static Pressure Analysis Von Mises Failure

Criteria Max stress=60.33 ksi

Ansys Stress AnalysisSolid Brick 8 Node

45Aluminum 7075T61/10th Scale ModelBoundary ConditionSymmetry

GeometryApplied Pressure =

22.176 Psi

Ansys Model

Free Meshing Deformation

VonMises Stress

c

Maximum Stress

Conclusion

Maximum stress: 21226 psiMax ultimate strength of material: >

75000 psiThe selected battery enclosure can

withstand the calculated explosion force: 22.176 psi

Boundary Fluent Boundary Type

Parameter and Value

Enclosure wall

Wall Adiabetic (heat flux = 0)

Battery module surface

Wall Constant heat flux1000 W/m2 (run 1)50 W/m2 (run 2)

Intake Inlet vent T air = 323 KOutlet Exhaust fan Δp = 3500 Pa

Fluent model boundary conditions

Fluent mesh

20C discharge rate

Velocity Streamlines

20C discharge rate

Aluminum

Grade Ultimate Strength (ksi)Price ($)

Ksi 4'x12' 4'x8'

2014T6 70 Unable to obtain unable to obtain

2024T3 58-63 $170.95 $114.54

7075T6 68-75 $153.95 $117.95

Al-2014T6 much rarer than expected Al-7075T6 is the strongest, then 2014T6, and then

2024T3. even with a higher ultimate strength, the price of

7075T6 cheaper than that of 2024T3 Aluminum 7075T6 chosen

Bill of Materials

ItemPurchasing Information Unit Quantity Price Total

Aluminum Sheet (t = 0.025") Grade = 7075T6 4'x8' sheet 1 $117.95 $117.95

Aluminum Sheet (t = 0.025") Grade = 7075T6 4'x4' sheet 1 $51.27 $51.27

BlastWrap (t = 1.0")   sqft 16 $16.00 $256.00

Toggle Clamp CL-500-PA piece 2 $64.00 $128.00 Fan  SF-90  piece 2 $2.50 $5.00 Vent   piece 1 $3.99 $3.99

Metal Feet Attachment   piece 4 $18.20 $72.80

Retractable Cord Apparatus 5000-30GF  piece 1 $33.00 $33.00

Total $668.01

Enclosing the battery pack safely, securely, and conveniently

Protection from accidental battery explosion

Reduces customer’s budgetSafety concerns of Toyota Plug-in Hybrid

customersSafety concerns of Toyota manufacture

Satisfied the majority of our sponsor’s requirementsFit in the trunk space and hold two battery

modules inside safely and securely Analysis

Hand calculations, Pro-Engineer analysis, Ansys analysis, and CFD analysis gave the team more confidence

Satisfied the cost requirement will help the future product to be

completed satisfactorily.

BlastWrap is such a new material, even they do not have many solid data points on their material Design and conduct small scale tests, utilizing the

BlastWrap during explosions Compare results to other scaled explosion tests that

do not utilize the BlastWrap. Possibility to prove its efficiency and more

Different material could be chosen for the outside of the enclosure.

Cheaper, lighter weight If tests show BlastWrap not

as efficient Choose stronger, heavier,

more expensive material Ensure customer’s safety.

Explosion analysis with softwareLive demoDynamic analysis

Ansys Analysis LimitationExplosion force simulationComputer limitation

Redesign of ventilation systemEliminate hot spots

Presentation on HPEV battery technology http://enerdel.com/pdfs/EnerDelTechnicalPresentation.pdf

Lithium Ion Battery http://electronics.howstuffworks.com/lithium-ion-battery1.htm

Jerry's Battery Box Jerry's battery box, used for competitive benchmarking http://jerryrig.com/convert/step10.html

Hymotion http://www.hymotion.com/

Hymotion Installed good view of installation http://www.hybridfest.com/images/26.jpg

About explosions by Aristatek equation for peak overpressure http://www.aristatek.com/explosions.aspx

Blast Wrap http://www.blastgardintl.com/pdfs/BLGA_AP_12805.pdf

Blast Wrap specs http://www.blastgardintl.com/bp_blastwrap.asp

Calculating overpressures from BLEVE (Boiling Liquid Expanding Vapor Explosion http://dx.doi.org/10.1016/j.jlp.2004.08.002

Vapor Cloud Explosion Estimates http://www.questconsult.com/99-spring.pdf

Vapor Cloud Explosion Estimates http://www.questconsult.com/99-spring.pdf

Dr. Hazim El-MounayriThrough out the whole project

Dr. Sohel AnwarProject Sponsor

Jack WaddellInformation of new product – Blast Wrap

Dr. Erdal YilmazCFD Analysis

TA. Rapeepan PromyooAnsys Modeling