Author Options:

Portable Homemade TV Answered

I built a TV from an old laptop screen and one of those LCD control boards you can get from eBay but I’m curious how to go about adding a battery to it to make it portable. So, my question is, how do I go about battery safety and how do I control charging and isolation? For example, if I plug the TV in because the battery is dead, do I just have a charging board between the input and battery and let the charging board take care of the rest? And the same question is applied to when the battery is at peak charge but I don’t want to use the battery just simply plugged in. The battery is a 12v 2A lipo and I don’t want any fires.

I’ve thought about adding a switch to simplify things but that’s inconvenient and armature
I could make a circuit that would cut off the flow when the battery is at peak I suppose but I’m not sure of the schematics or if that is the right approach.

I’m good at building just not figuring this stuff out….


The forums are retiring in 2021 and are now closed for new topics and comments.

Best Answer 5 years ago

Just an idea:
Get a proper charger for your battery (the digital kind with temp control and microcontroller for the charge control).
Between "TV" and battery put a low voltage protection, something simple like this should do:


To make it easy with the charging and mains supply you can use a switched power connector - similar to these headphone ones (when the plug is inserted a switch opens).

Depends on the input for the charger how complicated it will be.
If you find one that runs on 15 or 24V you can use a voltage regulator to use the TV from mains power and charge at the same time (here you disconnect the battery from the TV with the switch in the power plug).
If you have a mains charger than you need to add a power supply for the TV that is independent.
They can still share the same connection to the mains though.


Answer 5 years ago

In a way im lucky becabecause the tv board is 12v so i have a 12v 2A brick supplying and the battery im looking at comes with a charge cable. It looks like a simple charge concept and im assuming it has a temp switch similaf to a laptop battery but im not sure. Here is the link. http://m.aliexpress.com/item/32241463902.html

So if i understand correctly, the simpleat solution with the items im looking at using, I would have to use two mains supply, one for tv operations and one for charger when charging then just a simple jumper from tv to battery with voltage protection inbetween when unplugged from mains. Or to use on mains supply cram the dc brick into the unit and splice the input from mains to both brick and battery. Or a switched power connector..