> provide only about 4 to 8 hours of storage" (huh, what, why?)

Because the most efficient way to make money with a lithium ion battery (or rather the marginal opportunity after the higher return ones like putting it in a car are taken) is to charge it in the few hours of when electricity is cheapest and discharge it when it is most expensive, every single day, and those windows generally aren't more than 8 hours long...

Once the early opportunities are taken lower value ones will be where you store more energy and charge and discharge at a lower margin or less frequently will be, but we aren't there yet.

Advertising that your new technology doesn't do this is taking a drawback (it requires a huge amount of scale in one place to be cost competitive) and pretending it's an advantage. The actual advantage, if there is one, is just that at sufficient scale it's cheaper (a claim I'm not willing to argue either way).