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Power from USB?

Posted: Thu Mar 05, 2015 8:51 am
by Olwe
Can you "power" or "charge" the T430 through a USB like other devices (tablet, phone)? I'm looking at http://www.amazon.com/Poweradd-Pilot-Pr ... ql_qh_dp_t as a way to have on-the-go power.

Re: Power from USB?

Posted: Thu Mar 05, 2015 9:15 am
by brchan
T430 cannot be charged through a USB port, only through the DC port. However, the T430 has an 'always on' yellow usb port which can charge devices while in standby mode, or when powered off with AC adapter plugged in.

Re: Power from USB?

Posted: Thu Mar 05, 2015 10:00 am
by Olwe
So could an "external charger" like the one in the link could actually run the computer by being plugged directly into the T430's DC outlet (where you'd normally plug in the AC adapter)? If so, it seems you could eliminate the "middle man" i.e., the on-board laptop battery. I'm going on about this because there are solar power kits that have the solar panels that charge just such an "external charger." The laptop battery seems like dead weight if the external charger can provide what the laptop battery does. I'm looking at an old T61 battery and it seems to output 10.8V/4.4A. Does that sound right?

Re: Power from USB?

Posted: Thu Mar 05, 2015 10:16 am
by brchan
I doubt it would provide enough amperage to power the laptop. Also, thinkpads, at least the T400 and older thinkpads, will throttle the cpu if the battery is not installed, unless the AC adapter is 90 watts or higher. That goes for thinkpads with intel or nvidia/ati cards.

The OEM battery will probably be more reliable and go through more charge cycles before becoming unusable. Also, there is no need to reconnect a power source if the battery is already plugged in, as opposed to the product you linked in the description.

Re: Power from USB?

Posted: Thu Mar 05, 2015 10:29 am
by dr_st
So a laptop battery is more dead weight than this?
http://ecx.images-amazon.com/images/I/6 ... L1000_.jpg

Re: Power from USB?

Posted: Thu Mar 05, 2015 12:48 pm
by Olwe
So a laptop battery is more dead weight than this?
If you must have the external AND the laptop battery, then yes. This external is the "battery half" of a solar kit.
I doubt it would provide enough amperage to power the laptop.
Odd. It would seem like the external battery is merely replacing what your AC adapter does. So the next mystery is when you plug in your laptop (either the AC adapter or this external thing), is your laptop running on the "plug-in," or is it running on the laptop battery all along? It would seem the former, since you can disconnect the laptop battery with the laptop plugged in and it still runs.

In the case of tablets and other devices, I'm guessing being "plugged in" or not, it still in running on the battery. It would solve my "don't want to lug two batteries" problem if the T430 could be made to work this way.

Re: Power from USB?

Posted: Thu Mar 05, 2015 1:19 pm
by brchan
When the ac adapter is plugged in, the laptop will run on the adapter. Sometimes if the system detects that the power adapter is not providing enough power, it will also start using the battery. I do not think this is safe, though.