But how do I find out if an article is an ad or not?
1. Considering the source. IEEE Spectrum is a news and press release aggregation site. Look at other articles there. There is not a single good editorial, you can get the same content from CNN Technology News or 100's of other sources. There is nothing original there.
2. Article mentions the company name and no competition or comparative analysis. Ok, it drains battery in 25 years. What kind of battery? What was the best time to drain before that? It might have been 20 years, so Adesto's achievement is completely useless.
Also, there is no consumer battery that has 25 year shelf life, so what's the point of that?
IEEE Spectrum is not one of those "News aggregation sites"?!
Yes it is. IEEE name still has some reputation, but reputation does not bring in money, unless you sell it. That's exactly what they are doing with IEEE Spectrum.