Antimony
it allows the highest energy storage density of any material that can be used to make the plates of the battery from. this means small high power batteries.
a car battery is made of a plastic casing, lead plates and a sulfuric acid/water mixture
The electrolyte in a lead storage battery is a solution of sulfuric acid and water.
Sulphuric acid
The number of plates in a battery used for an inverter typically depends on the battery's design and capacity. For lead-acid batteries, common configurations include 2, 4, or 6 plates per cell, with larger capacity batteries having more cells and plates. In contrast, lithium-ion batteries usually come in modular designs and may not adhere to a plate count. Always check the manufacturer's specifications for the specific battery model to determine the number of plates.
Hydrometer
Metal isn't used at all, Automotive Batteries are made of plastic with lead plates, if it were just metal it wouldn't leas as the battery works off of electrolysis is the case was made of metal if would be corroded and eventually leak out all the acid. so to answer you question... NONE only lead for the internal plates, Stainless may potentially be used but lead is a cheaper and more common material in batteries
Because they will buckle if they are used dry.
It gives the battery the ability to store energy over a long period of time.
there is no restriction on the material used however it must be of a reflective material and white in colour for the front and yellow for the rear. Not all plates are Yellow front and White rear. For example German plates are embossed metal. The new french plates are printed.
Paper plates are made of paper. Paper used in making paper plates is made of mainly wood material.