For those of you new moms who never figured out how to heat up bottles in the car... we found a way
Get a thermos, fill with boiling hot water, and take an insulated coffee cup (or cup large enough to hold the bottle) with you on the road. Pour boiling water in the cup using your car cup holder and let the bottle sit for few minutes... voila! warm bottle!! Hubby has been so happy since we figured this out -- he can now run a full day of errands and LO never has to suffer with cold milk!
Tommee Tippee has a thermos/container system which does the same thing except it's HUGE (meant for their really wide bottles). My LO (and I think most BF babies) don't drink that much at each feed (DD drinks 2-2.5 ozs) so I use small Medela size bottles. Also the Tommee Tippee system won't fit in the car cup holder so you won't worry about splashing hot water on yourself! Amazon also has a ton of electric car charger systems but they all have bad reviews (breaks easily or takes forever to heat up). This system really works and is soo easy -- just thought I'd share