Lexus Repair: Battery CCA, cold cranking amps, engine displacement

Question
Hello:

I have what will probably sound like a fairly ignorant question, but since I don't know the answer, I need to ask someone.  I will be replacing my battery.  The recomended CCA's (cold cranking amps) for my car is a minimum 340,(4 cylinder car 2.2 liter engine) I have moved from Virginia (Warm climate) to Chicago (Cold climate), and since then have had some problems starting, and have had to charge the battery several times. So, I would l;ike to get a battery with a higher CCA. My question is, if I get a battery with a significantly higher than recomended CCA, can it do any harm to my electrical system?, IE. overload it, or does the alternator have to work harder to charge it, and perhaps need to be replaced sooner?

Thanks for your time, and please forgive the simpleness of this question.

Regards,

Morad

Answer
Hello Morad,   
 Cold weather will increases the strain on the battery, starting and charging system and tends to bring out any weakness of these components.  Cold weather thickens the oil and makes the engine hard to crank.  Your CAA will determine by engine displacement, compression and temperature.  I would have your charging system system check out. There is no point of upgrading the CAA if you can't find your orginal problem. Good luck and Enjoy the cool weather sir.  
           JPI