We have black outs every summer in CA. What happens when everyone charges their car all night?
Absolutely nothing.
Power produced must be consumed immediately. You can’t save it for later to power air conditioning or ovens.
When/if we do have massive battery energy storage it is the equivalent of massive capacity expansion. We can store any unused production for later when there is demand for it.
By the way what is the cost per kWh and power density of these new aluminum ion batteries? Commercialization requires a balance of metrics. What companies don’t tell you is usually a disqualifier.