Cell Phone and Bluetooth Battery Life

April 16, 2007 10:36 AM

Would a new Bluetooth headset reduce my cell phone battery life by 75%?

I have a Treo 700w which I've really enjoyed. I just this weekend purchased a Motorola Bluetooth headset (Model H350). Pairing was non-eventful and easy.

Usually my 700w can go a good 2 days between charging, even with heavy usage.

This morning, I started with a full charge, and have used the phone once for about 10 minutes. Now at lunchtime it looks like the battery is almost depleted. I toggled the Bluetooth off to see if I could make it through the day.

Should a Bluetooth headset be draining that much power from my handheld? Is something misconfigured?

Surely I don't need to toggle the bluetooth setting on/off everytime I want to use the headset? That would significantly cut into the convenience of this item.

posted by Ynoxas to technology (8 comments total)

No, it should not have that dramatic of an impact. Do you have your phone set to "discover" mode (on my Moto it's called "Find Me" in the bluetooth menu)? I believe that uses more power, because it broadcasts its existence, rather than just listening for connections.
posted by chundo at 11:20 AM on April 16, 2007

If you've had Bluetooth disabled prior to purchasing the headset, and then you enabled it after your purchase, it's quite likely that is causing your decreased battery life.

By the way, it's not the headset that draws power from the phone, it's the Bluetooth application itself.
posted by NYScott at 11:26 AM on April 16, 2007

Look at it this way - enabling the Bluetooth on the device is turning on another peice of hardware, yet another radio.

In my experience, coming from 3-different Bluetooth-capable devices - enabling Bluetooth reduces battery-life by 50-75%, even without using the headset.
posted by jkaczor at 11:51 AM on April 16, 2007

I bought a bluetooth headset to use with my motorola v551 awhile back and as I recall, it did create a noticeable change in battery life. I don't think it was 75%, but could have been close to half.
posted by justkevin at 12:09 PM on April 16, 2007

Chundo: Currently the "make this device discoverable" is not checked, but it is possible that I still had that checked from the initial pairing. Hmm. I MEANT to turn it off yesterday but I honestly do not remember. I'll retry tomorrow making sure that setting is turned off.

NYScott: Yes, I've always had BT disabled until yesterday. And I worded that poorly, you're right of course the headset physically doesn't draw power from the handset... I meant what you said, the application.

Since it has to have some sort of broadcast and receive mechanism I expected SOME battery loss, but since the battery has been so robust in the past I didn't expect a problem.

on preview: jkaczor: that's exactly what I'm seeing. Maybe that's "just the way it is".
posted by Ynoxas at 12:11 PM on April 16, 2007

It seems to depend on the phone. The bluetooth transceiver on my Sony-Ericsson T-610 would shorten battery life, but by maybe 30%, and that was with auto-discovery turned on. I haven't used it much yet, but the transceiver on my Motorola RAZR V3 so far depletes its battery faster. It's hard to quantify by casual observation.
posted by ardgedee at 1:53 PM on April 16, 2007

When I have Bluetooth enabled on my RAZR, even on standby without using the headset, I've found that my battery life is DRAMATICALLY lower. So now I just turn it on when I intend to use the headset, and my phone stops dying every few days - I get a good 3-4 days without recharging (I don't talk on it much :))
posted by antifuse at 1:27 AM on April 17, 2007

Thanks everyone.
posted by Ynoxas at 7:36 AM on April 18, 2007