Sign-in / Sign-up
Your question

Laptop Battery as UPS

Tags:
  • Laptops
  • Product
Last response: in Laptop General Discussion
September 29, 2008 1:58:45 PM

Hi,

Sorry if this topic has been raised already. I did a search for "battery" which returned zero results. Clearly something is wrong with the search function...

In any case, here's my scenario: I've acquired an old but good laptop (Dell Inspiron 8500, Pentium IV) that will solely be used for music. I'll be connecting it to my home stereo, and I won't be moving it anywhere, or using it for anything other than for playing music. My music files are stored on an external USB hard drive (powered externally). I also have a USB sound card (USB powered).

In case of power outage, or just for sake of maximising the longevity of the equipment, it would seem best to have a battery back up / UPS. If the power goes down, I can shut off the computer and hard drive properly, with minimal risk of data loss.

That makes good sense for the external hard drive. Laptops, however, have their own batteries and therefore a UPS would seen redundant.

Therefore my question: Is there anything wrong keeping the old battery in my laptop for use as a UPS? The charge may last 5 minutes, which is in fact all the time I need. Is an old battery somehow damaging to a laptop? Should I simply inspect it periodically to make sure it's not overheating?

Buying a new laptop battery is expensive and seems a waste, given the low price I paid for the laptop. The other alternative is taking out the laptop battery and buying a UPS that could support both the laptop and the hard drive. I'd rather not, unless I absolutely have to. Besides, with an external UPS, the laptop will not know the power is cut, unless I install special software and add one extra USB connection.

Any advice? Is it OK to simply keep using the old laptop battery and buy just a tiny UPS for the external hard drive?

Cheers

More about : laptop battery ups

a b D Laptop
September 29, 2008 5:14:40 PM

I'm not quite sure what you're getting at. Do you want to use the laptop battery as a UPS for the external hard disk?

If you want to use the battery as a UPS for the notebook itself (in other words, making the battery perform the function it was designed to do) then that's fine.

You could use the battery to power the external hdd and the system at the same time, but that's quite a bit of modding, and I'm not sure how the notebook would stand up to the reduced power. You'll have to disassemble the battery and make new connectors for the notebook's motherboard.

Use the external hard disk as both the music storing disk and the system disk by using your laptop's ATA connection. They make connectors that convert the mini ATA cable to a standard one. Then using a 12v power supply along with a series of AA batteries, with a small transistor switching circuit in between, you can make a UPS for the hard disk.

All in all, I think this is a lot more trouble than it's worth. How often does the power go out anyway? What are the chances it goes off while you're using that machine, while the machine is doing a critical read/write on that disk?

September 29, 2008 6:26:24 PM

I might be being over cautions.

The power doesn't go out totally very often, but as other appliances get turned on and off there are occasional problems. This is why I wanted to get a UPS---especially for the hard drive that has all my music on it.

My real question is, is it OK to keep using the old battery in the laptop? It doesn't hold a long charge, but it holds 20 min of charge, which is just fine for my purposes, as I detailed.

Are older batteries somehow "bad" to use? Do they run particularly more risk of leaking or overheating?

Or, is it better to run the laptop without the battery?
Related resources
a b D Laptop
September 29, 2008 10:44:26 PM

Alright - I didn't understand what you meant.

The battery is fine the way it is - it's not going to cause any issues, as long as it doesn't start randomly rebooting the machine, which I have seen happen. But in my experience, most older laptops work fine with their crappy batteries.
October 1, 2008 2:17:48 PM

Although, it is a Very Good Idea(tm) to use a UPS anyway (especially one that also protects RJ45 and Coax/RJ11-- depending on your connection type.

I know three people, including myself that, lost a lot of equipment due to power surge over Coax or RJ45 (well, the RJ45 was from an outdoor wireless antenna being struck my lightning. . . fried the router, switch and every computer connected via Cat5 at the time.)