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15 to 85 % SOC at 80 mA/cm2 with an energy efficiency of 83% and an energy content of 1.4 kWh. A picture of the assembled and tested redox flow battery system is shown in Figure 1. Tank Transfer pump Pump 1kW Stack 1kW / 1kWh VRFB System Figure 1. 1 kW / 1 kWh VRFB system and 1 kW stack The kW scale VRFB with the PNNL mixed acid electrolyte successfully demonstrated stable, reliable and efficient operation without any precipitation - even at electrolyte temperatures > 45°C. This high temperature operability provides several unique advantages including: 1) high electrochemical stack efficiency due to better kinetics and low electrolyte resistance, 2) low viscosity resulting in lower pump power loss, and 3) no need of heat exchanger system. The aforementioned benefits also increase the system energy efficiency and enable simplification of system designs and control, resulting in overall cost reductions. Cost analysis for a 1.0MW / 4.0 MWh system were based on the performance of the prototype stack and project to a system level cost of $540 /kWh when assuming a 20% installation cost and current material technologies. Overall, the prototype system exceeded the performance goals of 1.0 kW at 80mA/cm2 and energy efficiency of > 70%- while meeting the cost target of < $560/kW. In FY 13, PNNL demonstrated a 1 kW/ 1kWh scale prototype stack and system with double the previous current density (160 mA/cm2 vs 80 mA/cm2). The stack utilized a Nafion 212 membrane which is approximately half the thickness and cost of the conventional Nafion 115 used in state of the art redox flow battery systems. A new interdigitated flow concept was also developed using modeling and experimental techniques to attain an increase flow of up to 3-4 times the original design while maintaining the same pressure drop. The resulting stack exceeded target metrics by achieving 2.4 kW at 160 mA/cm2 with an energy efficiency of 79%, nearly 5% greater than previous stacks, and a system efficiency of 72%. In FY 14, PNNL demonstrated 4 kW/ 1 kWh scale prototype stack and system with 50% greater current density than FY 13 (240 mA/cm2 vs. 160 mA/cm2 in FY13). The battery utilized the OE developed all-vanadium mixed acid electrolyte and a Nafion 212 membrane. At 240 mA/cm2, the stack achieved ~ 5X increase in discharge power over FY13 objectives (4.9kW vs. 1kW) while operating at ~ 75% energy efficiency. In addition to using lower cost membrane materials, the stack employed a novel interdigitated design and lower pressure drop manifolds Stack 6PDF Image | High Current Density Redox Flow Batteries
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Salgenx Redox Flow Battery Technology: Salt water flow battery technology with low cost and great energy density that can be used for power storage and thermal storage. Let us de-risk your production using our license. Our aqueous flow battery is less cost than Tesla Megapack and available faster. Redox flow battery. No membrane needed like with Vanadium, or Bromine. Salgenx flow battery
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