Electrolytic caps are manufactured to various quality standards and ratings for operating temperature range and other electrical characteristics, including performance at higher frequencies and effective series resistance (ESR).
Cheaper commercial grade caps are typically spec'd to work at temperatures up to 85 deg. C. Industrial grades are spec'd to 105 deg. C.
In power filtering circuits, caps act as A.C. shunts to ground while blocking D.C. In an ideal capacitor, the effective series resistance is infinite at D.C. and eventually reaches 0 ohms at some frequency determined by its value and the impedence (resistance) of the power source.
In a less than ideal cap, any residual resistance is called "effective series resistance" (ESR), and any power lost by current passing through it is dissipated as heat, which in turn can cause component failure if it exceeds the design spec of the part.
Another cap characteristic is D.C. leakage, which means that a non-ideal cap exhits some D.C. resistance value less than infinity, resulting in power loss and power dissipation.
Electrolytic caps are among the least ideal of capacitor technologies for ESR and leakage, and their ESR tends to degrade further at higher frequencies, which is why caps spec'd for switching power supplies and circuits that operate at verh high frequencies, especially those with limited space and cooling, i.e. computers and digital signal processors such as video cards, digital entertainment media, etc. require better grades of caps.
If you want to replace the caps in your TV, start by knowing the values and voltage ratings of the caps. If the original caps aren't damaged (burnt, exploded, etc.) to the point where the manufacturer and model aren't readable, you can go to the part maker's site to get specs for the original component. That will give you a guide to the minimum specs you'll want for a replacement.
If the original caps spec'd by a manufacturer were marginal for voltage ratings, going to the next higher voltage rating will give the circuit an extra safety margin. In most cases, a slightly larger cap value won't hurt, either, as long as the specific circuit isn't a tuned design intended to be resonant at a given frequency, which is not the typical case for power filtering circuits.
The physical size of a capacitor is larger for both greater values and higher voltage ratings so there is always the matter of which available part will fit in the space of the part your replacing. OTOH, capacitor technology has improved significantly in recent years. Larger cap values with higher voltage ratings are getting smaller, and the newer solid electrolyte caps exhibit remarkably better specs.
Finally, I don't want to discourage those who are willing to try, but I don't recommend doing this, yourself, unless you're experienced enough at soldering to know what a good, clean solder joint looks like and even more experienced at removing old parts without damaging the circuit board and surrounding components... or unless you're willing to sacrafice your TV on the altar of self-education. You could damage more than you fix and trash an otherwise repairable TV.
Hope the info helps. Good luck.
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