https://hackaday.com/2025/09/17/when-is-your-pyrex-not-the-pyrex-you-expect/

Basically pyrex spun out of Corning Glass, enshitified and use soda lime glass (shit) while Corning retained PYREX which is still high quality borosilicate glassware (often with a blueish tint).

“The result surprised even the research group: compared to pure barium titanate of a similar thickness, the current flow was up to 1,000 times stronger, despite the fact that the proportion of barium titanate as the main photoelectric component was reduced by almost two thirds.”… So not actually 1000x better than current technology, just 1000x compared to pure barium titanite. Garbage clickbait, but “clever technique applied to ineffective solar cell technology scrapes 1% efficiency when used in UV spectrum” does not have the same appeal.

Are you going to wire the solar to a usb connector and plug it into the bank charging port? This is probably the safer way of approaching this.

Also, sometimes the quoted voltage is a “nominal working voltage” kind of deal. Grab a multimeter and see how many volts the solar cell puts out at noon without any load, it might be in the 8v range that could pose an overvoltage problem to your bank (that’s expecting 5v ) if it fills up completely.