The Development and Utilization of New LFPO Battery
2012-12-19 10:44
Green-energy industry flourishes upon the development of diverse renewable energy applications that present a wide range of renewable energy solutions being customized by systems tailor-made for different market segments. Lithium battery cell and battery pack are two vital applications that each plays a critical role in the renewable energy supply chain, Chang Hong is a Lithium-Iron battery cell manufacturer that has insightful experience and unique perspectives about the industry.
Environmental-Friendly Procedure
Chang Hong has its business developed mainly based on battery cell production, which comprises of lithium polymer batteries that came in both 16.8Ah and 50Ah (composited of three cells as shown in Figure 1). The company adopts LFPO (lithium iron phosphorous oxide) as the cathode material throughout the water-based manufacturing procedure. In contrast to the adoption of tradition LiFePO4 oil-based procedure, the prior is safer and more environmental benign. Water-based method can avoid possible explosion risks arise from the organic solvents, which could be flammable and toxicated, derived at the later part of the manufacturing process. The selection of cathode material thus plays a critical role and places a direct impact over the manufacturing process security, equipment investment, and product yields.
Figure 1. Lithium iron phosphate oxide battery cell from Chang Hong
Source: Chang Hong, compiled by TrendForce
Since the molecular structure of the LFPO battery has the defected Olivine nature, safety issues for high temperature resulted from overcharged or discharged application may be eased and less to worry about. Lithium that is extended has a different motion pattern with the existing Lithium electrode materials such as cobalt, which confirms that LFPO ensures the security of large input/output current. The LFPO battery, guarantees a life cycle of over 2,000 recycles, has no doubt to be the best product among all lithium batteries . Circuitry design is also being simplified as the composition of four LFPO battery cells can replace the 12V from lead–acid batteries.
Outstanding Electricity Discharge Performance
Constrained by its particle density nature, weight difference between LFP/LFPO and Li(Ni-Mo-Co) based Lithium battery has always drawn concerns. To ease such concerns, Chang Hong produces 50Ah prismatic battery by a composition of individual cells, which makes the battery 20% less in weight and 30% less in size as compare with the same-capacity 18650 Lithium battery, using 45 cylindrical cell connection in parallel(Figure 2). Lesser soldering points in between cells also guarantees a more stable current flow.
In terms of discharge performance, Chang Hong’s LFPO battery delivers a maximum current of 500A (10c, pulse 30 seconds) with power density also surpasses 1413w/kg, making its LFP/LFPO battery outstanding in terms of its compact size and high capacity.
Figure 2. The side view of a power storage system
Source: Chang Hong, compiled by TrendForce
Diverse Utilization
The company has strengthened ties with fellow module makers for a full-extent use of its high-capacity 50Ah battery cell. The battery cell has been successfully deployed into power system for use in various applications including lamp, vehicle, bicycle and ferry.
In the vehicle segment, Chang Hong aims to focus on Europe, Japan and the US scooter markets by its current collaboration with fellow scooter vendors. The company also offers customized solutions for use in golf car, bus, electric vehicle, etc. In addition to the diverse battery cell utilizations, Chang Hong also deploys into the energy storage system segment with Japan and Europe being the key markets. The solutions are targeted for areas with unstable power supply and energy-saving application.
Where for the ferry segment, the cell that is being adopted by the reservoir water-inspection boat, Shihmen Number One, has already in pilot run at Shihmen Reservoir in Northern Taiwan. The company expects to introduce the power system into patrol boats for use in other reservoirs or water-protection areas such as the Sunmoon Lake in central Taiwan in the next three years.
Figure 3. Battery for use in various applications
Source: Chang Hong, compiled by TrendForce
Manufactured by the ship maker, Chia Sheng Yu enterprise,supported by Lung-Ye enterprise to construct the catamaran base, designed by Ship and Ocean Industries R&D center with Hung-Chang Corporation’s carefully developed electrical control technology and battery design,the first solar-power mission boat, Shihmen Number One, installed with Taiwan made key components, has begun its water-inspection service in September.The R&D team, which is composited by several key vendors, has taken full advantages of LFP/LFPO battery to meet service mission. Its design has optimized battery use by addressing requirements from the listed aspects: environment (water- and shock-resistance in high humid environment), motor voltage, emergency power system, electric-control system, solar-power introduction, battery selection/composition and power management, power system and water-tight design.
Shihmen Number One has two power sources – one 60KW electric battery as the primary source and the photovoltaic (PV) panel as the second. There is 16 pieces of 3kW PV panels mounted on the boat roof to for power storage. The Northern Region Water Resources Office of MOEA (Ministry of Economics Affairs) indicated that the boat carries the mission to promote clean energy with 16 routine inspection tasks being assigned, said authority director Chang Ting-Hua. The authority will strengthen its collaboration with volunteers for the clean-energy concept education.
Figure 4. Shihmen Number One
Source: Shihmen Reservoir management authority.
Based on the field survey, Shihmen Number One is designed for calm waters in terms of the boat size and weight. In contrast to just re-model ordinary yacht by changing engine, Shihmen Number One is customized in catamaran design(Figure 5). The vacant part at the boat bottom reduces water resistance, while only minimal surface area contact against the water. The new design will allow engine to run more efficiently with an extended sailing time.
Shihmen Number One is equipped with a total battery capacity of 60kWh. By having six individual modules connecting in parallel, sailing will not be affected when any module malfunctions. In contrast to the general 220v motor, the boat is powered by two 25kW (96v) low-voltage motors, running on a low-power 6kW (~about 6 knot). By adopting a high-capacity 50Ah battery cell design on the mentioned low-power motor, battery c-rate (capacity rate) is reduced to 0.1c. The efficient capacity rate thus in turns helps saving power for the battery heat dissipation module and making the design simple.
The battery is charged on high voltage at 16kW (220v, 75Ah) with each charging time requires an approximate of four hours. The battery can also be charged by secondary source at the meantime– the photovoltaic (PV) panels that mounted on top of the boat roof. So when the boat is sailing, the battery is actually being charged by the sunlight.
[Figure 5. Component features of Shimen Number One]
Source: Chang Hong