If I could get a ceramic capacitor at the capacitance of 10uF and within my voltage requirements, which from my initial searches I can, what problems would I experience if I were to change, if any?
Some circuits (like some linear regulators, for example), require a certain minimum ESR from the output capacitor, which could cause the circuit to oscillate when using a ceramic but not with an electrolytic.
In a precision circuit, a ceramic might not be preferred due to microphonics, but in those cases you probably wouldn't want an electrolytic either.
Otherwise, ceramics are generally preferred. They'll have lower ESR, they're not polarized, they need less voltage de-rating, and so on.
Finally, when searching SMD footprint standards, the common packages seem to be 0402, 0603, and 0805, where they increase in physical size respectively, but also power rating, which suggests to me I should use as large of a package as possible
Usually you choose the smallest package you can get away with because you want to fit as much circuit as you can in the smallest footprint.
Also, for ceramics, the larger sizes (1210 and higher) can have reliability issues because they can be cracked if the board flexes.
No. A capacitor only has one charge. The charge creates a voltage differential to the capacitor. From the positive pin, the voltage is negative towards the other pin. From the negative pin, the voltage is positive towards the other pin. What you suggest would mean that there would need to be 3 pins and two capacitors.
It would help a little if you would tell us what you are trying to do, exactly. If you are trying to make a negative voltage, that can be done by switching to which nets the pins of the capacitor is connected to. Let's say you need to generate -5 volts from +5 volts. You can charge the capacitor between the +5V net and ground, then disconnect the capacitor, and then connect the + pin of the capacitor to the ground. The - pin of the capacitor now has -5 volts, when compared to ground.
As you discharge the capacitor, the voltage at the - pin will change towards the ground; from -5 volts to -4 volts, from -4 volts to -3 volts and so on. So you will need to switch the way the capacitor is connected again, and charge it from between the +5 volts and ground. This system is called a "charge pump".
Best Answer
It IS possible to store high voltage energy, and probably possible to built a store that would not be destroyed by the first lightning strike. BUT even the biggest cap easily available will store less energy than a 2500 mAh NimH AA cell. Many such capacitors would allow significant energy to be stored "at a strike" but the store cost would be large.
It would be possible to construct capacitors capable of say 10's of kV rating which were protected [tm} by spark gaps so that the gap broke down well below capacitor destruction voltage. You would then potentially (pun noted) have a problem with back conduction of the capacitor via the ionisation path, but could very probably build a system that used a spark gap from input to capacitor to initialise charging and then another spark gap from input to ground such that it reduced the available potential of the charging spark gap and extinguished the arc. While this sounds rather "Heath Robinson" it is similar to the sort of things that are really done at extra high potentials.
As an example of spark gaps being used as switches, a "Marx Generator" uses arc breakdown to cause spark gaps to act as switches and allow construction of a voltage multiplier witj DC input. Good trick if you can do it. You can ! :-)
See "Marx generators below.
Capacitors:
You can make DIY multi kV capacitors aka "Leyden Jars - with glass jars or bottles - or even plastic "pop" bottles. From here
Here's a 19 nF 10 kV cap made with foil and mylar shopping bags
You can buy capacitors in the nF range rated at 10's of kV.
Many offered here - Alibaba
Example from above - 40 kV, 10,000 pF disk ceramic.
At 40 kV 10 nF will store 8 Joule. About the same as a 0.64F cap at 5 Volt.
Many very high voltage caps here - very worth looking at
1.3 uF at 100 kV !!!!!!!!!! :-)
6500 Joule.
Less than the energy in a 2500 mAh AA NimH cell (= about 10,000 J)
Marx Generators - as examples of spark gap switching.
This video of a 180 kV output Marx Generator operating is worthwhile just for the sound :-).
I am NOT suggesting that a Marx generator is what you need to meet your suggested requirement - but offering it as an example of how switching may be achieved by quite unusual but eminently practical means.
Wikipedia - Marx Generator
The following is far from the most impressive spark-gap-switch unit image available - I chose it because it gives a good view of the spark gap switches working (small arcs along the centre line) plus the resultant overall multiplied voltage arc (you should be able to find that without my guidance :-) ). To make this work you only need a voltage able to break down the small spark gaps.
Worthwhile
LOPT in, 200 kV out](http://c4r0.elektroda.eu/_hv/index.php?page=hv/marx) Polish language.
Project with image
Very good project description.
"Quick & Dirty" Marx generator
Karl would have been proud!