Toyota Avalon Starting?

[hayes55987 0]

Got a question about the electrical of a 2000 Toyota Avalon. I don't have a system in there (still debating about that), so currently its a completely stock 2000 Avalon. I am not having any "electrical" problems but the starting is a little bit slower then I'd like and with winter coming up shortly I don't wanna be stuck with a slow starting car. What happens is that the car will take a bit to start up when its "cold", but if its only been off for a bit, it takes a bit longer to start-up. The interior lights on the dash will dim when i have the brights on and like..put windows up for example. Is this a sign of bad electrical? What are some options that I can do to speed up starting? Or is this something thats not even an electrical issue?

I was thinking maybe just a new battery and the big 3? I don't think a new alternator would have any need as I don't an actual system in the car. The lights dim when i put up/down windows and the lights are all on, but this happened with my 1997 Camry as well. Maybe just a Toyota thing?

So the questions I'm asking are:

Should I upgrade the battery and big three? just battery? just big three?...whats the cheapest option I can go with

Secondly, does this sound like a problem with electrical? or is it spark plugs or something like that that can't be solved with electrical upgrades?

[KU40 173]

Does it crank easily when you start it but just not turn over or does it have a slow crank too? If it cranks but just doesn't start it's not a battery problem and could be starter, fuel delivery, etc. Slow crank is indicative of not enough electrical power. Is your voltage where it should be?