Honestly, sometimes yes and sometimes no — it depends entirely on your usage, and you should model your own numbers rather than trust a blanket claim either way. A battery earns its keep by storing daytime solar (or cheap-rate grid power) and letting you use it instead of buying expensive units in the evening. The home where that pays is one with real evening load, a tariff with a cheap charging window, and enough consumption to cycle the battery most days. The home where it struggles is low-usage, daytime-empty, with little evening load to displace — there the battery sits half-used and the payback stretches past its warranty.
What's changed in 2026 strengthens the better case: with dynamic (half-hourly) pricing now live, a battery plus a bit of automation can chase several cheap windows a day rather than a single fixed night rate, and can occasionally even pay to discharge into a price spike — widening the arbitrage beyond the old "fill at 8–14c, run the evening off it" model. That tilts the maths a little more in the battery's favour for engaged users on the right tariff.
Two caveats keep it honest. First, don't oversize: a battery far bigger than your daily cycle just lengthens payback, and the money is often better in extra panels. Second, batteries are warrantied for a number of cycles as well as years — sensible daily cycling is fine and won't exhaust the warranty, but thrashing it purely to export at a low rate isn't worth the cycles. Bottom line: model your own half-hourly usage, size to your evening load, and treat a fast payback as a bonus, not a guarantee.