On the far left we have the original Swan Morrison 14V 24 Amp issued Generator. This was replaced in the late 80’s with the Yamaha EF 1000 which provided Master posts with 240 volts and 800 watts of power. The Yamaha EF 1000, as far I know, was not issued to standard posts. The last image is of the original post batteries. These were “Submarine Batteries”. They are a nickel-cadmium (NiCd) type, made by Alcad, (they are still producing batteries).The plates within being made from an iron gauze containing Cadmium particles and the other plate is similar but with Nickel. Cadmium is highly toxic and difficult to dispose of. Their cell voltage is nominally 1.2V (lead acid is 2.0V). This is why there are 10 cells in the 12V bank rather than 6. They would in all probability still take a charge and even recover fully given a few charge/discharge cycles. Charging voltage is higher than lead acid, explaining why the Swan Morrison Generator outputs at 14 volts. They are very long lasting and resilient batteries. Care would have to be taken should they ever be brought back into use. Renew the rubber seals and fill with new electrolyte. If the level is low and you can see the plate structure above the water-line, they can be topped up with demineralized/de-ionized water. Beware of buying top-up water from car shops though – they often contain a weak acid additive intended for lead acid batteries. This would wreck the cells and probably fizz up out of the filler holes!
In the interests of Health and Safety though, I’ve opted to use leisure batteries which you can see in the very bottom of the picture.