To the credit of the Malaysian system, for all the layers of favoritism enjoyed by the Barisan Nasional incumbents, the distilled gripe was allowed to be expressed.

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Once you get funding for a mass system it can have all sorts of layers of user protection and sophistication in matching built in.

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But for the process to result in a working battery, all five layers must stick together and work in synchrony, and the tricky step was finding a separator material that kept the whole stack in one piece.

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