Energy Storage Advancement LiFeYPO4 as replacement for Lead-Acid Lithium Iron Yttrium Phosphate (LiFeYPO4) February 2016
Summary & Conclusion For the same Price today; retailing @ $550/kWh (daily useable) Buy Lithium Iron Phosphate (LFP) instead Lead Acid equivalent Lithium Iron Phosphate (LFP) delivers same kwh/day as Lead Acid BUT: LFP lasts 2-4 times longer (10-15 years) 10 year warranty < 25% of the weight < 33% volume No gasses or acid 100% safe 100% environmentally friendly
Can LiFeYPO4 replace equivalent Lead-Acid?
What is LiFeYPO4 vs Lithium-Ion? A lithium-ion battery (sometimes Li-ion battery or LIB) is a member of a family of rechargeable battery types in which lithium ions move from the negative electrode to the positive electrode. Wikipedia.com 154 references Tesla Motors Lithium Cobalt Oxide(LiCoO 2 ) Lithium Manganese Oxide (LiMn 2 O 4 ) Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO 2 or NMC) Lithium Iron Phosphate(LiFePO 4 ) Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAlO 2 ) Lithium Titanate (Li 4 Ti 5 O 12 ) BlueNova
What is the Y in LiFeYPO4? Yttrium in the cathode High electron transfer at low temperatures Increased capacity at low temp High C ratings at low temperatures Protects Iron Phosphate molecular structure from oxidation layer damage during high temperature applications
Considerations for a Changeover Same Price or lower Same Performance or better More Operating Cycles More Usable Life Just as or more Safe Weight must be lower Preferably Smaller Easy to Dispose and Recycle
Which Lead Acid Batteries are we looking at? Deep Cycle Batteries 30% - 50% DoD to give 1500 3000 cycles at 25 degree C Peukert coefficient of at least 1.3 or better (low loss during discharge) 3-5 year warranty 5-7 year life 16.5:1 Battery 50% DoD Cycles (Wh)Namplate rating Source Price $/kwh Trojan 6V, 189Ah 1800 1134 Iron Edidon 352 310 Trojan 6V, 189Ah 1800 1134 Battery Stuff 320 282 Raylite 6V,570Ah 1600 3420 sustainable.co.za 748 219 Trojan 12V, 150A 1200 1800 sustainable.co.za 250 139 Raylite 6V, 600Ah 1500 3600 sustainable.co.za 639 178 Lead Crystal 12V,200Ah 2000 2400 offdrigdiy.co.za 411 171 Hoppecke 2V, 280Ah 2500 426 ecosolarspain.com 157 367 Hoppecke 2v,730aH 2500 1092 ecosolarspain.com 260 238 Hoppecke 2v, 1520aH 2500 2880 ecosolarspain.com 476 165 Rolls 12V, 166Ah 1800 1992 ecosolarspain.com 339 170 Rolls 12v, 180aH 1800 2160 ecosolarspain.com 443 205 Rolls 12v, 266aH 1800 3192 ecosolarspain.com 499 156 Avarge Price $/kwh Retail prices $217/kWh
Sizing a LiFeYPO4 battery 123 Lead to Lithium 1. Adjust Lead-Acid Ah rating for Depth of Discharge (LA= 50% and LiFePO4=100% ) 2. Adjust Lead-Acid Ah rating for Discharge Efficiency (25% more losses than LiFeYPO4) 3. Adjust Lead Acid Ah rating for Adjust for Terminal Voltage (5% lower) Ah (LiFeYPO4) = Ah (LA) x 50% x 75% x 95% = 36% 100Ah 50 Ah (50%) 37.5 Ah (80%) 35.6 Ah (95%) Step 1 Step 2 Step 3
Step 1 : Depth of Discharge (DoD) Aim for 1800 cycles 1800 cycles give approx. 5 years daily use Operating temp at 25C Discharge at C/10 Hoppecke = 50% DoD, 2000 cycles @ 25 degrees C DoD = 30% to 50% Use 50% https://www.victronenergy.com/blog/2015/03/30/batteries-lithium-ion-vs-agm/ http://pqrs.co.za/april-2015-lifepo4-vs-lead-acid-batteries/ http://www.solara.de/en/products/storage-solutions/hoppecke/ When compared to lead acid batteries being around 65% Empirical data has demonstrated efficiencies as low as 55% in a residential PV system where the Depth of Discharge (DoD) is limited to 20% as a measure to lengthen the life of the lead acid cells.
Step 2 : Discharge Efficiency Lead Acid 50% University California Santa Barbra
Step 2 : Discharge Efficiency LA Capacity loss due to discharge current C5/C100 = 60% C10/C100 = 70% C20/C100 = 77% Voltage efficiency = 2V/2.3V (voltage / cell) = 87% Discharge efficiency = 70% x 87% = 61%
Step 2 : Discharge Efficiency LA Capacity loss due To discharge current C10/C100 = 80% Voltage efficiency = 2V/2.3V (voltage / cell) = 87% Discharge efficiency = 80% x 87% = 70%
Step 2 : Discharge Efficiency LiFeYPO4 Discharge Efficiency : C/2 = 96% 2hrs charge cycle https://www.victronenergy.com -12,8-Volt-lithium-iron-phosphate-batteries Discharge Efficiency : C/2.5 = 96% 2.5 hrs charge cycle https://www.bluenova.co.za BN52V-3.6kHC LiFePO4
Step 2 : Differential Discharge Efficiency Lead Acid = 60% - 70% LiFeYPO4 = 96% Differential= 26% to 36% Use a delta of 25%
Step 3 : Terminal Voltage kwh = Vbatt x Ibatt x t LA = 12.4 Volt LiFePO4 = 13 Volt LiFeYPO4 current = 95% of Lead Acid current LiFeYPO4 (Ah) = 95% of Lead Acid (Ah)
123 Lead to Lithium Check 123 Lead to Lithium 1. Adjust Lead-Acid Ah rating for Depth of Discharge (LA= 50% and LiFePO4=100% ) 2. Adjust Lead-Acid Ah rating for Discharge Efficiency (25% more losses than LiFeYPO4) 3. Adjust Lead Acid Ah rating for Adjust for Terminal Voltage (5% lower) Ah (LiFeYPO4) = Ah (LA) x 50% x 75% x 95% = 36% 100Ah 50 Ah (50%) 37.5 Ah (80%) 35.6 Ah (95%) Step 1 Step 2 Step 3
123 Lead to Lithium Conclusion on Price Lead Acid cost $200/kWh on nameplate value Usable kwh of Lead Acid cost $200/0.36 = $555/kW BlueNova - LiFeYPO4 retail at $550/kWh
Reality check on battery life The optimum operating temperature for a Lead Acid battery is 25 C (77 F); every 8 C (15 F) rise above this temperature threshold cuts battery life in half. http://batteryuniversity.com/learn/article/lead_based_batteries
What about charge efficiency? Utility Generator Solar PV Wind Turbine 26% less kwh to charge LiFePO4 Charge efficiency = 70% vs. Charge efficiency 96%
Charge Efficiency of Lead Acid Batteries A Study of Lead-Acid Battery Efficiency Near Top-of-Charge and the Impact on PV System Design John W. Stevens and Garth P. Corey Sandia National Laboratories, Photovoltaic System Applications Department Sandia National Laboratories, Battery Analysis and Evaluation Department Photovoltaic Energy Technology Division of the US Department of Energy 100Ah Trojan 30XHS battery charge and discharge at C/30. Charge SOC % Efficiency 50 60 85% 60 70 80% 70 80 70% 80 90 60% 90 100 40% Avg Efficiency 67%
Charge Efficiency of Lead Acid Batteries Jens Bäcker Larry S. Meisner Head of Product Management Managing Director and V. P. Technology Reserve Power HOPPECKE Batteries Inc. HOPPECKE Batterien GmbH & Co KG Cherry Hill, NJ 08034 59929 Brilon, Germany Charge Efficiency = 71.7%
Charge Efficiencies of LiFeYPO4 batteries Charge Efficiency : C/2 = 96% 2hrs charge cycle https://www.victronenergy.com -12,8-Volt-lithium-iron-phosphate-batteries Charge Efficiency : C/2.5 = 96% 2.5 hrs charge cycle https://www.bluenova.co.za BN52V-3.6kHC LiFePO4
Nett effect of charge efficiency? 26% less 26% less kwh to charge LiFePO4 Charge efficiency = 70% vs. Charge efficiency 96%
LiFeYPO4 Safety Safety Performance for Phosphate Based Large Format Lithium-Ion Battery, John Nguyen and Chas Taylor Valence Technology Fire Test Nail Test Lithium Ion batteries for storage: LiMn2O4 - lithium-manganese LiCoO2 - lithium-cobalt LiNiO2 - lithium-nickel These battery have shown thermal events under certain conditions. Short Circuit Test LiFeYPO4 has shown no thermal events under any test conditions. www.bluenova.co.za/safety
Size and Weight LiFeYPO4 Size < 30% of Lead Acid Voltage Ah Wh Weight (kg) Lead Acid 12V 200 2 400 50 LiFePO4 13V 66 864 13 Lead Acid 48V 3 461 166 111 3 461 LiFePO4 52 1 150 59 800 780 LiFeYPO4 weight < 25% of Lead Acid
Environmental impact and Recycling RoHS Compliance (Restriction of Hazardous Substances. Directive 2002/95/EC) Lead Acid : Violet status. Contains Lead and sulphate LiFeYPO4 is RoHS compliant Lead acid: Needs special recycling after treatment utility LifeYPO4 : No recycling required, can re-use copper and aluminium.
Summary & Conclusion For the same Price today; retailing @ $550/kWh (daily useable) You CAN buy Lithium Iron Phosphate (LiFeYPO4) instead Lead Acid equivalent Lithium Iron Phosphate (LiFeYPO4) delivers same kwh/day as Lead Acid BUT: LiFeYPO4 lasts 2-4 times longer (10-15 years) 10 year warranty < 25% of the weight < 30% volume No gasses or acid 100% safe 100% environmentally friendly
Product Range (Residential / Commercial)
Product Range (Custom) Voltage Range Ah Range Voltage Range kwh Range 13 46 13 0.6 15.0 26 69 26 1.2 29.9 39 115 39 1.8 44.9 52 184 52 2.4 59.8 104 230 104 4.8 119.6 upto 345 520 23.9 598.0 812V 460 812V 37.4 933.8 805 1150
Product Range (Industrial/Utility scale) Large format LiFeYPO4 prismatic cells 1000Ah up to 10,000Ah 900kWh up to 9MWh
8.1 MWh, 1.4MVA @ 4hrs BESS PowerPlex AEG SC600 800kW 70% DoD 5.7 MWh per cycle Cycle twice daily for 10 years with 20% fade C/4 charge & discharge R1.50/kWh fixed for 10 years
Useable Storage Capacity = 4.1 MWh (min) DoD = 75% Cycles = 7000 (can cycle twice daily) Charge rate = C/4 Discharge rate = C/4 Operating Temp = -10 C to 55 C Round Trip Efficiency > 96% Average Usable Storage 3.7MWh (10 years)
Questions?