TU-TESL

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According to foreign media reports, recently, the U.S. Army filed a patent application. Researchers Ernest luoto, Brian frymaire and David Carrier developed an intelligent controller that can control the power distribution of solar panels to the battery, thus preventing tens of thousands of car batteries in the parking lot from slowly failing. It is estimated that the technology can save millions of dollars for customers. The U.S. Army has a huge fleet of tens of thousands of wheeled combat vehicles deployed in military bases around the world. Among them, 75% of the multi-purpose wheeled vehicles (Humvee), anti mine anti ambush vehicles (MRAP), light Medium Tactical Vehicles (lmtv) and 5-ton trucks travel less than 3000 miles per year. Because these trucks spend most of their time in the parking lot, the lead-acid batteries they are equipped with will slowly run out and degrade. To keep these trucks on standby, the U.S. Army spends $26 million a year replacing batteries. "Data from the latest army sample data collection and analysis (SDC & A) report shows that on average, the combat vehicle battery needs to be replaced every 13 months, but the minimum life expectancy of the battery is three years. If properly maintained, the battery life is expected to reach about six to eight years," the researchers said If solar energy is used to charge the battery, the life of the car battery can be extended three to five times, saving the army 17 million dollars every year. However, most of the military trucks are equipped with powerful radio and other electronic systems, powered by series and parallel 12V and 24V batteries. For example, some trucks need four 120 amp large batteries to output 12V and 24V power, but the battery pack on the vehicle has different loads, which will cause voltage imbalance. The research shows that the voltage difference between two 12V battery lines is not rare, but 1V voltage difference will produce a huge difference between 100% full charge or about 20% full charge, which limits the use of solar charger. As a result, researchers have developed pulse width modulation controllers that turn solar panels on or off, move them between cells every hour, and prevent cell sulfation and overcharge.