Actually- 99% of modern electronics not only don't need a pure sine wave inverter- many don't even need AC at all!!This system of solar panels, and batteries, suppling mains quality electric, is common on Narrowboats', all be it small scale.
What is needed is a good understanding of how to charge the batteries properly, Lithium batteries, have very different requirements to Lead acid.
Good quality Pure Sine wave inverters' are needed for modern electronics. A proper multi stage battery charger, to maintain the batteries over winter, as Solar panels produce next to no charge during the British winter, and the batteries will suffer great damage if left less than fully charged, over that period.
Seriously- anything with a switchmode power supply in it (that 100-250v 50/60hz label on it) will run straight from the DC battery bank of many modern offgrid houses- which often run at 96 or 120vDC, some even higher...
With modern offgrids being so large (10kw, 20kw or even more) of panels and 10kw+ inverters- the days of a 24 or even the 48v banks has passed (I bought my 48v 12kw inverter cheap, because not many offgrid systems here in Oz are that low any more...)