LiFeYPO4 as replacement for Lead-AcidLithium Iron Yttrium Phosphate (LiFeYPO4)

January 2016

Energy Storage Advancement

• 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

Summary & Conclusion

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

Lithium Cobalt Oxide(LiCoO2)Lithium Manganese Oxide (LiMn2O4)Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2 or NMC)Lithium Iron Phosphate(LiFePO4)Lithium Nickel Cobalt Aluminum Oxide (LiNiCoAlO2)Lithium Titanate (Li4Ti5O12)

Tesla Motors

BlueNova

What is the Y in LiFeYPO4 ?

Yttrium in the cathode• High electron transfer at low temperatures• Increase capacity at low temp• High C ratings at low temperatures

• 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

Considerations for a Changeover

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 $/kWhTrojan 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

$217/kWhAvarge Price $/kWhRetail prices

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%

Sizing a LiFeYPO4 battery

100Ah 50 Ah (50%) 37.5 Ah (80%) 36.5 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

• 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/

DoD = 30% to 50%Use 50%

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.

University California Santa Barbra

50%

Step 2 : Discharge Efficiency LA

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

https://www.victronenergy.com -12,8-Volt-lithium-iron-phosphate-batteries

Discharge Efficiency : C/2 = 96% 2hrs charge cycle

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

LiFeYPO4 = 96%

Differential= 26% - 36%Use a delta of 25%

Lead Acid = 60% - 70%

Step 3 : Terminal Voltage

LA = 12.4 VoltLiFePO4 = 13 Volt

LiFeYPO4 current = 95% of LA currentLiFeYPO4 (Ah) = 95% of LA (Ah)

kWh = Vbatt x Ibatt x t

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

Reality check on Cycle 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

vs.

Charge efficiency 96%Charge efficiency = 70%

26% less kWh to charge LiFePO4

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

Efficiency

50 60 85%

60 70 80%

70 80 70%

80 90 60%

90 100 40%

67%

SOC %

Avg Efficiency

• 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 of Lead Acid Batteries

Charge Efficiency = 71.7%

Charge Efficiencies of LiFeYPO4 batteries

https://www.victronenergy.com -12,8-Volt-lithium-iron-phosphate-batteries

Charge Efficiency : C/2 = 96% 2hrs charge cycle

Charge Efficiency : C/2.5 = 96% 2.5 hrs charge cycle

https://www.bluenova.co.za–BN52V-3.6kHC LiFePO4

vs.

Charge efficiency 96%Charge efficiency = 70%

26% less kWh to charge LiFePO4

Nett effect of charge efficiency ?

LiFeYPO4 Safety

www.BLueNova.co.za/safety

“Safety Performance for Phosphate Based Large Format Lithium-Ion Battery”, John Nguyen and Chas Taylor Valence Technology

Lithium Ion batteries for storage:• LiMn2O4 - lithium-manganese• LiCoO2 - lithium-cobalt• LiNiO2 - lithium-nickelThese battery have shown thermal events under certain conditions.

Fire Test Nail Test

Short Circuit Test

LiFePO4 has shown no thermal events under any test condition.

Size and Weight

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 Size – 30% 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

• LiFePO4 is RoHS compliant

• Lead acid: Needs special recyclingafter treatment utility

• LifePO4 : 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 (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

Product Range (Residential / Commercial)

Product Range (Custom)Voltage Range Ah Range Voltage 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

kWh Range

Product Range (Industrial/Utility scale)

• Large format LiFeYPO4 prismatic cells• 1000Ah up to 10,000Ah• 900kWh up to 9mWh

Questions ?