Solar Power Battery Bank Using NiCads
And if you want to buy a new set, you will need to be on really good terms with your bank manager, these things are expensive.
Wet cell NiCads are used in jet aircraft, and electric powered commuter trains as a couple of examples. As a result of regulations being in place, these batteries are required to be replaced after a certain period of time. And since it is entirely possible that these batteries are in perfect condition, there is no reason that you might not find a set. Especially if you go looking hard enough.
I think the worst bugaboo is the maintenance that is required.
The day to day, or more like week to week maintenance such as adding distilled water when necessary takes but a few minutes. And if you are not in the habit of discharging the batteries too far, you may only have to add distilled water every few months. That is the easy part.
NiCads have a kind of memory. Just like the ones in your rechargeable flashlight and so on.
They get to a point where they will need discharging and recharging completely. This will take you quite some time, as the batteries must have the voltage monitored carefully during the discharge process.