Rechargeable Dendrite-Free Zinc Anode RANGE ANNUAL REVIEW 8 9 - PowerPoint PPT Presentation

DE-AR-0000391 A New Dimension in Energy Rechargeable Dendrite-Free Zinc Anode RANGE ANNUAL REVIEW 8 – 9 January 2015 Principal Investigator Michael Burz, CEO, EnZinc, Inc. Technical Principal Investigator Debra Rolison, U.S. Naval Research Lab 1

TEAM: Rechargeable Dendrite-Free Michael Burz, CEO, EnZinc: mburz@enzinc.com Zinc Anode Team Member: U.S. Naval Research Laboratory Technical PI: Debra Rolison Current Status Technology Overview 1. PROVEN: dendrite-free cycling 1. Develop a non-Li EV battery based on ü >80 cycles at 40% DOD Zn NRL’s 3D Zinc sponge electrode in fully >100 start – stop duty cycles ü rechargeable Ni – Zn cell configuration & ü 5-cm 2 pouch cells running demonstrate dendrite-free cycling at Li- 2. EVALUATED: Electrolytes to enhance competitive depth-of-discharge (DOD) ZnO precipitation 2. Projected cost-competitive (<$180/kWh) 3. EVALUATED: for e-bike | start – stop | BEV with Nissan Leaf Li-ion at 100 kg lower 4. NEXT TECHNICAL: Scale-up to 25 cm 2 @ weight 100 cycles 5. NEXT COMMERCIAL: Obtain strategic 3D Zn sponge Create fully metallic, partner for commercial deployment highly conductive 6. HELP NEEDED: Sourcing high-capacity pathways in 3D NiOOH cathode improve current → distribution 1 – 6 mm suppress dendrite Project Statistics → thick formation Award Amount $452,358 Award Timeline March 2014 – March 2015 Next-Stage Target Battery Scale-up Collaborations Sought Hi-Capacity Cathode Supplier Strategic Partner

Down-selected electrolyte composition Tested six electrolyte compositions → two selected • thinned 1-cm 2 Zn sponge disk Post-cycled Pre-cycled Zinc Zinc Sponge Sponge 3

Dendrite-free cycling to 40% DOD Zn • Demonstrated >70 cycles of 3D Zn sponge anode versus two-ply harvested NiOOH in prototype cells ( cycling 40% DOD Zn terminated when capacity 20 mA cm – 2 (160 mA g – 1 Zn ) fades to 20% DOD Zn ) NRL electrolyte #1 Cycling ongoing 77 cycles @ 40% DOD Zn 40% DOD Zn 5 mA cm – 2 (40 mA g – 1 Zn ) 4

NiOOH – 3D Zn: Start – stop duty cycles Constructed Duty Cycle to Evaluate Pulse Power 5 min • Steady load of – 5 mA cm – 2 4 h 1 h 2.5 h • Two pulses of – 75 mA cm – 2 for 5 s 15% DOD Zn 10% DOD Zn • One pulse of – 25 mA cm – 2 for 15 min 15 min • 12% DOD Zn , 63 W h kg – 1 in packaged cell • 109 total cycles (one month) Step C rate C rate mA cm – 2 (anode only) (packaged cell) † 5 s 5 s – 5 C/25 C/10 – 25 C/5 C/2 † Assuming 40% – 75 C/1.75 1.5C theoretical DOD Zn 1.8 discharge voltage (V) 1.7 – 75 mAcm – 2 5 s 1.6 – 25 mAcm – 2 1.5 15 min 1.4 NRL electrolyte #2 0 100 200 300 400 time (s) Elapsed cycling time (h) 5

Zinc Sponge Anode Delivers Performance Start – stop/ E-bike Low-range EV Microhybrid Li-ion AGM SLA Ni – 3D Zn Ni – 3D Zn (Nissan Ni – 3D Zn (Trojan 12) Leaf) Energy Capacity 540 540 1720 1720 24000 24000 (Wh) Weight 12.2 5.9 45.0 21.7 339 220 (kg) Specific Energy 44.3 91.8 38.2 79.2 71 109 (Wh kg − 1 ) Energy Density 140 225 126 164 96 216 (Wh L − 1 ) 6

Zinc Sponge Anode is Cost Competitive 300" Average'Ba)ery'Cost'$/kWh' 250" 200" Margin" SG&A" 150" Labor"&"Other"Costs" 100" Material" 50" Lead 0" Acid Li)Ion" Ni)3D"Zn" ($/Wh/cycle) Price to Use Li-Ion 3D Zn-Air 3D NiZn 400 0 100 300 200 Low High Usable Stored Energy (Wh kg − 1 ) 7

Mandatory and Additional Information DE-AR-0000391 Dendrite-Free, Rechargeable Zinc Sponge Anode 8

Summary of Major Accomplishments • Achieved dendrite-free cycling of 3D Zn sponges ü >80 cycles at 40% DOD Zn • Demonstrated >100 start – stop duty cycles • Fabricated pouch cell ü 5-cm 2 Zn electrode + harvested NiOOH cathode ü Molds procured for 25-cm 2 Zn electrode (seedling deliverable) • Performance & cost analysis show Ni – 3D Zn competitive to existing lead-acid, Ni – MH, Ni – Zn & Li-ion batteries 9

Lessons Learned • Limited cell DOD arises from low-capacity NiOOH commercial cathodes • Obtain only ~ 20 DOD Zn % per one-ply cm 2 of NiOOH harvested from commercial AA Ni – Zn cell Identified electrolytes to enhance ZnO precipitation at • 3D Zn surfaces Established protocols to incorporate 3D Zn sponges in • practical cell configurations Collaborations sought: Technical & T2M • Require source of high-capacity NiOOH cathode • Provide >75 mAhcm – 2 of NiOOH cathode (to match 60% DOD Zn of 1-mm – thick Zn sponge) 10