When a crash is detected and the airbags are deployed, is the SAE Battery Field Discharge and Disconnect Comthere are several other systems in the vehicle that are also mittee. triggered. For example, the fuel pump is disabled, and in While their intention is to promptly find solutions, we the case of EVs, the high voltage connection is opened can only expect committees to move so quickly. As the between the battery and the rest of the vehicle. So, any conversation evolves, Charged will keep you posted on event that causes the pack to go into what is known as any expected new standards. “safe shutdown mode� would also cause a discharge. After the contactors open to disconnect the high voltage, then it would initiate this discharge internal to the battery. It would have to be at a slow rate, because of the heat generated, but the idea is that a small amount of heat would be safer than leaving the stranded energy. This solution could also solve the problem of delayed thermal events, because damaged vehicles would not be stored, for any amount of time, with charged cells that could react with their surroundings. There are a few concerns with the internal safety circuit concept. Is it feasible to implement, and at what cost? Just like any safety system, it would have to be designed robust enough to function as intended after severe crash condiPUT YOUR TESTING IN HIGH GEAR tions. That could get expensive. Also, if the battery has been damFor more than 20 years, Arbin Instruments has aged, would it further comprobeen developing industry-leading testing mise safety to initiate energy flow solutions for the battery, supercapacitor, and fuel cell markets. Arbin systems deliver extremely within the pack? Would it be safer accurate results at unmatched data collection to leave it stranded? speeds. From low-power, single-cell testers to These are tough problems that regenerative EV systems capable of thousands of need to be solved as soon as Amps, Arbin products are meeting the needs of possible. In addition to the ANSI companies around the world. panel, the standards community With more than 3000 systems running in more gathers groups of experts into than 50 countries, Arbin has established itself as smaller committees to concentrate the global leader in battery testing equipment for on individual issues. The SAE every application. International Battery Steering Committee is focusing on delayed Contact Arbin today to see how our systems can battery overheating events. For help bring your testing up to speed. the issue of stranded energy, there
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