Should car be idling when I am charging my laptop?

[masvx800]

The reason your laptop battery takes 1 hour+ to charge isn't because it's soaking up so many Amp*hours (a unit of energy) but because it has to do it slowly enough that it won't heat up too much by getting charged at too high a rate (energy / time = power). Heat can damage batteries. So you should be ok if you only use your car battery a few times to charge your laptop. Also, if you're using an inverter (turns DC from car into AC for a wall charger, you'll use more energy to charge the laptop battery than if you just use a DC charger your laptop may also have. That's because the inverter might waste up to 40% of the incoming energy turning it into AC.

I also recommend starting your car every couple of days or so and letting it run for a while, maybe even at slightly higher rpm so the alternator's kicking out more amps to push into the car's battery.

 

[followingmybliss]

We plan on camping early next spring in an area with no electricity. I will need to be using my laptop, and have bought a charger that plugs into the cigarette lighter of our 1999 minivan.

What I need to know is how do I charge my laptop daily without wearing down the car battery?? Do I let the car run while I'm charging it?? Charging can take at least an hour. How many days in a row can I do this without hurting the battery??

Any tips on how to do this will be so appreciated!

 

[JohnPaul]

There are 2 to 10 amp photovoltaic cell 12 to 15 volt car battery chargers Northern Tools sells that will keep the van charged in the sun that way you won't have to run a internal combustion motor. Also many lap tops can charge directly fron a cigarette lighter with out the need to step up the current with a adapter cigar lighter power outlet to 120volts. Check the maker of your computer web site My HP adapter was around 70 dollars and takes 10 to 24 volts 11 amps max and converts it to 19.5 volts 4.82 amps to charge the HP battery. Using a 120v transformer will draw much more Amperage and drain the van battery much faster. With a Computer made charging cable you may recharge one time a day from your van battery and still drive away. Just run the van to the camp store or at a high idle around 1,500 rpms15 minutes everything turned off in the van for the second lap top charge. The Solor Panel idea would eliminate the need to run the van to recharge the battery. And If I had to take modern world along I would stay home anyway. Oh that's what I am doing! I carry my Lap top on my bicycle and car almost won't leave home with out it. Note car batterys like a high draw and rapid recharge Unlike lap top batterys that like a slow drain and slow recharge. Repeted charges with out recharging the van battery will leave your van dead.

 

[HeyThere1]

i charge and use my laptop from my cigarette lighter for a while now, never had a problem with the battery, even when charging for hours while car is off.