Release: June 7, 2012
NGK INSULATORS, LTD.
NGK INSULATORS, LTD. has announced the cause of the fire that occurred on September 21, 2011 involving the NAS (sodium-sulfur) batteries for electricity storage that it has manufactured. NGK also announced safety enhancement measures and the resumption of factory operations.
NGK has worked to find the cause of the incident and implement countermeasures since it happened. Recently, a third-party investigation committee, with Japan's Hazardous Materials Safety Techniques Association serving as secretariat, reviewed the cause of the fire and containment measures, and judged that the details regarding both were reasonable and appropriate.
Based on the results of this investigation, NGK decided to voluntarily implement safety enhancement measures, including a monitoring system, under the guidance of the Fire and Disaster Management Agency.
By implementing these safety enhancement measures, customers can be assured of their using NAS batteries with even greater peace of mind because the batteries now have more safety features than previous ones.
Up until now, NGK has asked almost all customers to suspend using NAS batteries or to restrict their usage. NGK is working so that these batteries can be re-used after quickly implementing safety enhancement measures according to installation conditions, while following the guidance of the fire authorities having jurisdiction in the installation locations.
The main details of the cause of the fire and safety enhancement measures are as follows:
Since the fire incident, NGK has suspended operations at its NAS battery factory in Komaki City, Aichi Prefecture, Japan. However, operations will resume at this facility from June 2012 now that the cause of the fire has been investigated and safety enhancement measures devised.
For the time being, the plant will put priority on reforming NAS batteries that continue to be used by customers. However, NGK plans to commence production of new batteries in the second half of the current fiscal year, which starts on October 1, 2012.
NGK deeply regrets any worry or inconvenience that may have caused to customers and other concerned parties by the fire incident.
Global demand for large-capacity electricity storage batteries has continued to increase, driven mainly by the utilization of renewable energy, smart grids, and government energy policy reviews.
Looking ahead, NGK will work to implement safety enhancement measures and raise quality further as it works on customer service, while expanding business in NAS batteries, which have garnered high marks for their large capacity and highly efficient electrical storage capacity.