Industrial Battery Overview Lead Acid Batteries are under increasing threat from Lithium (ion) in a number of traditional areas such as standby and cyclic markets. Lead Acid batteries have been replaced in newer markets such as PHEV’s and increasingly in electric bikes. BATTERY ENERGY VIEW: Lead acid batteries will continue to dominate if:- a)Cost and not energy density is important, and b)Customer technical and commercial requirements are met or exceeded.
Customer Technical Requirements Good starting performance Good float Capability Excellent cycling performance Good resistance to abuse Fast charge capability PSOC (partial state of charge) capability Long life – especially in inclement conditions Standard footprint
Rail Market Traditionally uses vented traction batteries or some Ni-Cad for starting and standby applications. Newer requirements are for:- Minimal maintenance Passenger compartment security Long life (>6-8 years) Cycling at low states of charge
Traction/Utility Market Newer requirements are for:- Fast charge capability PSOC capability Opportunity charging In Traction - Long life/low cost (3-4 years) at double shift In utilities – Long life/low cost (>10 years service)
Solar/Raps Market PSOC capability (20 – 30% daily DOD) Good abuse resistance capability System predictability > than 10 years service life ONLY ADVANCED SUPERGEL BATTERIES CAN MEET ALL THESE REQUIREMENTS.
Battery Energy Gel Battery Programme Battery Energy Gel Battery Programme Started 1992 with CSIRO*. Worked with them and others through to mid 2000’s. Programme aim – to develop sealed gel batteries at similar cost to vented but with major performance advantages. *Commonwealth Scientific & Industrial Research Organisiation
SuperGel Technology The basis for the Battery Energy SuperGel Technology is as follows:- In jar formation – provides lower cost, improved OH&S and performance advantages Optimised paste mixing/curing process Thick plate technology (5.3mm positive and 3.9mm negative) High fumed Silica concentration (6%) Optimised material selection process (VRLA lead, corrugated separators) GEL PRODUCTS INTRODUCED COMMERCIALLY 1996
Gel Programme Achievements Battery Energy has developed a sealed SuperGel battery with high conversion of active material in formation The final products are characterised by:- a)High degree of Ah efficiency (102 – 103%) b)Capable of PSOC operation over long periods of charge/discharge cycles with minimal overcharge. Starts out at 101%, probably 102% at end of life
Float Performance Characterised by:- - Very low float currants - Good high rate performance - Typically 2-3 times longer life on accelerated tests compared to AGM
Battery Energy SuperGEL Float Currents OperatingTemperature Degrees C° Cell Voltages Per 100Ah in mA
Cyclic Performance (1) Initial CSIRO test results 1200 cycles at 100% DOD – failure due to negative plate. Positive plate - 14% corrosion after 800 cycles. High temperature tests (45 degrees) 555 (100% DOD) cycles – no loss of capacity.
Cyclic Performance (2) PSOC ETEC (US) 2001 – fast charge/PSOC 70% DOD (100% - 30%) - >1000 cycles. Battery Energy SuperGel is 2-3 times life of competitor gel products. ETEC Current testing – utility profile 80% - 30% SOC ~ 2000 cycles and still operating. AGM batteries 300 – 400 cycles under same profile. Solar – PERU ILZRO – RAPS daily ~ 35% DOD (80% - 45% SOC) in 240Vstrings. Still operating after 7 years (requirement 8 years).
Abuse resistance Overcharge – 2.6V for 8.5 months ~ 3 times longer than AGM battery. Operating in the discharge state - charge to 2.45V/discharge to 1.75V – battery walks down to 30% SOC. 150 – 200 cycles (PSOC without equalisation). Recovery process – 100% capacity X 2. Water loss – much less than other batteries. (See next slide for example) No stratification observed.
Water loss Data Duty Battery type Tem p. (°C) RWL gev (ml/Ah/cell/year) WL crit (ml/Ah/cell) Years to reach WL crit (with WL corr50 ) Simulated 1-day RAPS service CSIRO (o) * CSIRO (o) * (m) * (m) (n) (n) Field service (m) * (n)
Conclusion Advanced SuperGel technology together with advanced control techniques and further battery optimisation will lead to a bright future for industrial lead acid batteries. Independent of lithium battery technology advances
BATTERY ENERGY Australian Made Products, Designed for the harshest of Australian Conditions Australian owned company, employing Australians. QUESTION TIME?