Lead Acid Batteries

1. Lead Acid Batteries

2. Optima Batteries Acquired in November 2000 by JCI • Plant located in Aurora, Co • Optima Batteries utilizes six sigma methodology • TS 16949 Certification • Worldwide distribution

3. Lead Acid Battery Basics

4. Battery Basics-Definitions • A battery is a device that converts chemical energy into electrical energy. • A cell is the basic electrochemical unit. • A battery consists of one or more cells connected in series, or in parallel, or both. • Batteries, in general, are classified as primary, i.e., non-rechargeable, or secondary, i.e., rechargeable. Zinc-manganese dioxide, LeClanche’ or alkaline, cells are primary batteries. Lead-acid batteries are secondary batteries. Advanced secondary batteries include nickel metal hydride and lithium ion. • Types of lead-acid batteries include round or cylindrical and prismatic or rectangular cells. • Lead acid batteries can be classified further as wet, i.e., flooded,or VRLA (valve regulated lead acid) which includes gel and AGM (absorbed glass mat).

5. D D D C C C Battery Basics-Cell Chemistry • At the positive plate: PbO2 + 4H+ + SO42- + 2e- PbSO4 + 2H2O • At the negative plate: Pb + SO42- PbSO4 + 2e- • Total Cell Reaction: PbO2 + Pb +2H2SO4 2PbSO4 +2H2O Note: Active materials include lead dioxide, lead and sulfuric acid. Note: Battery OCV depends only acid specific gravity andthe cell voltage can be approximated by V = 0.84 + acid specific gravity.

6. Battery Basics-Cell Chemistry Additional Reactions of Significance • Oxygen Reaction Cycle:: ½O2 + Pb PbO PbO + H2SO4PbSO4 + H2O Note:Oxygen reaction cycle is a benchmark characteristic of VRLA batteries. It is more pronounced with AGM than with gel constructions. • Severe Overcharge Reaction: 2H2O O2 + 4H+ + 4e- Note: This results in water loss due to venting of O2 and can be life limiting. • Positive GridCorrosion: Pb + 2H2OPbO2 + 4H+ + 2e- Note: This results in water loss and can be life limiting. C C C C

7. Load Power e- e- e- e- Electron Flow Electron Flow ─ + ─ + Oxidation Reduction Reduction Oxidation Anode Cathode Cathode Anode Pos Ions Pos Ions Neg Ions Neg Ions Electron Loss Electron Gain Electron Gain Electron Loss Discharge Charge Battery Basics-Cell Schematic

8. Battery Basics-Manufacturing Wet/Gel/AGM

9. Manufacturing-Wet/Gel Yes No

10. Manufacturing-AGM Flat Plate

11. Manufacturing-AGM Spiral Wound

12. Grid Production Processes Gel Spiral AGM Wet & Flat Plate AGM

13. Grid • Grid • Primary function is structural to support the active material and carry the current • Secondary function is electrochemical in nature as the grids participate in redox reactions at the positive and negative active material interface, i.e., corrosion • Desired features • Low resistivity • Strength • Corrosion resistance for positives • High purity

14. Grid Alloy • Grid Alloys • Lead/Lead Tin • Soft, generally too weak to use in flat plate designs • Low gassing • Low self discharge • Continuous grid making processes for spiral wound design • Lead Calcium Silver • Low gassing • Low self discharge • Slower processing compared to lead antimony • Lead Antimony • High gassing • High self discharge • Easily cast and fabricated • Good cycle life

15. Paste • Paste • High Paste Density • Stronger material with less shedding in wet or gel designs • Shedding is not an issue with AGM designs because of the compression of the separator against the plates and the tight interference fit with the cell container • Better contact with the grid interface • Reduced initial capacity which cycles up to give longer service life in cycling applications • Lower efficiency at high discharge rates • Low Paste Density • Initial capacity is high • Higher efficiency at high discharge rates • Poorer service life in cycling applications

16. Separator Distinctions Gel AGM Wet

17. Separator Sources • Separator • Wet • Microporous polyethylene envelopes • Extrusion formed • Backweb thickness • Oil content • Silica content • Gel • Microporous polyethylene sheets • Polyvinyl chloride sheets • AGM • Glass microfiber sheets • Compression is an important design feature • Glass-polyolefin composites under development • Made on conventional paper making equipment

18. Separators From BCI Website Wet Optima

19. Wet or flooded vs AGM IT’S THE SEPARATOR AGM = Absorptive Glass Mat Flooded is “Vented” Gas exchange with surroundings AGM is “Sealed” Valve regulates pressure and vacuum

20. Wet/Gel Battery Construction From BCI Website

21. Optima AGM Battery Construction • Optima has lower internal resistance compared to flat plate batteries • Optima has less internal parts (~30) vs traditional batteries (120+) • Optima has over the partition, solid lead connectors vs through the partition inter-cell welds

22. Element Characteristics • Factors affecting internal resistance of the battery • Size of lead conductors • Plate surface area • Plate spacing • Separator resistivity • Electrolyte type • Gel has higher resistance than flooded or AGM designs which negatively impacts high rate and cold performance • Electrolyte concentration • Temperature

23. Cylindrical cells provide superior mechanical structure to battery Eliminates cell bulge Permits higher valve pressures, 7-8 psi, compared to flat plate, 1-5 psi Flat plate batteries can experience end wall bulge when pressure builds up on charge resulting in loss of performance Container/Cover Design

24. OPTIMAPerformance

25. What is Optima? • Advanced lead acid battery technology • Spiral wound cells • Sealed AGM design • Current OE applications • Daimler Chrysler • Minivan Diesel (Graz, Austria) • PT Cruiser Diesel (Toluca, Mexico) • Jeep Liberty Diesel (Toledo, USA) • FORD • GT • GM • Silverado Military Truck

26. Orientation Flexibility • Non-Spill • Can be installed in almost any orientation/position • Air shippable like gel and flat plate AGM

27. Vibration Performance The Optima Advantage Vibration Resistance • The Optima Group 31 runs in excess of 9,000 hours at 5G’s Why? • High degree of separator compression, and tight interference fit between the element and cell wall • Less parts, two plates per cell vs. multiple plates in flat plate designs • No intercell welds to fail Source: AGM Development Team

28. Gassing Characteristics • Gassing • Less than flat plate/prismatic design • Why? • Higher purity materials – 99.99% pure lead • Alloys – Optima uses a binary tin lead alloy compared to a flooded battery that uses a multi component alloy (silver, tin, calcium, aluminum, etc… less impurities) • Oxygen reaction cycle Source: AGM Development Team

29. OCV Stand Loss OCV STAND LOSS

30. More Power Optima has more high rate power (CCA) than comparably sized flat plate batteries Why? Higher specific acid gravity than flooded Lower internal resistance than flooded due to thinner positive plates than flooded and no inter-cell welds High Rate Cold Performance

31. High Rate Cold Performance High power, more run time gives Optima more available energy -20Degrees F/300 A Discharge

32. High Rate Cold Performance

33. High Rate Cold Performance

34. Performance on Charge

35. 155 Min RC/75 A-hr C/20 Optima Group 31 185 Min RC/98 A-hr C/20 Flooded Group 31 Repetitive RC Cycling @ 80 F Repetitive Reserve Capacity Cycle Life

36. Field Returns Battery life increases with cooler temperatures AGM has longer life in warm temperatures Typical flooded expected life DecreasingTemperature