I would like to be able to play games on my insprion 15 7000 while on road trips, but it's power hungry and the car's cigarette lighters are 120 watt, so the 130 watt charger won't work. I was wondering if I could use an inspiron 14 5000 charger (75 watts or something close to that) to make my laptop last a little longer without destroying the charger by pulling too much power. Thanks in advance for advice.
I've been unable to find evidence you can use a lower rated charger - and absent Dell designing a slow charge mode (which they have on some models), this would hopefully not work - again dependent on Dell design - as it would be a bit dangerous.
The laptop could try pull more current then can be delivered, causing stress on the power brick componentry and which could anyway overload the 10 amp socket it's connected to (causing wiring to possibly heat up, but hopefully blow the fuse).
I actually had a coworker who took his Dell workstation laptop on a business trip and complained to me on Skype the whole trip about how slow his laptop was running, and all kinds of weird problems (restarting randomly, graphical artifacts, strange Windows errors). When he got back I noticed he was not using the 180W power supply that came with the laptop, but rather a 130W power supply that he had from his computer at home. He was all like "well the plug fit so I thought it was the same..."
So the moral of the story is: It might work to some degree, but you're risking damage to your computer and data corruption in the files saved on it.
You could try something like a Yeti 400 battery pack and solar panels to recharge it. That would definitely be able to power your charger.