I have to leave our Lexus es350 for 6 mos at a time. in our garage. Is it better to disconnect the battery or put a trickle charger on it?

 

Frequent discharging and recharging a battery will cause premature failure. Buy a battery tender and leave it on for 6 months. I do it every year on my classic Corvette.
Cost about $35.00... No reason to disconnect battery and lose all memory functions on the car...

 

Another vote for the battery tender, super cheap and prevents a lot of headaches in the future

 

we have a trickle charger for car batteries is ok

 

 

I vote for disconnecting the battery, unless you have a house sitter to watch over the car. I hate leaving electronic equipment on for a long time unless it's necessary. I would even hate to leave the fridge on for for six months - again, unless there is a house sitter The charger can short and start a fire; why risk it?

 

Battery tender on mine while we are gone for 5 months.