Thinkpads Forum

What have people found to be the best way to charge the ThinkPad tablet?

I've found that the wall USB charger can be fairly slow to charge the device. Additionally, charging from a computer USB (even a high voltage "always on USB" on a T410) is a complete non starter.

I assume this due to the very low power supply potential of USB (default is 5V at 500mA or 2.5 watts) compared to the comparatively high power requirements (at least 7-10 watts [probably more while charging]) of the ThinkPad tablet.

This is mainly a problem because I have found that standby is draining power far faster than it should (as in from 100% to 0% in only a few days with no use).

Has anyone found a faster or better way of charging the slate tablet? I'd rather not buy the "dock" just to be able to charge this thing (although I have plenty of 65w and 90w adapters lying around). I'm curious of ways both at home and while travelling.

Also, does the actual quality of the microUSB cable matter at all? I have not been able to successfully charge my tablet with the microUSB cable that came with my phone even though it seems comparable to the cable that came with the tablet.

The USB cable is of utmost importance. I don't know the technical details but some cables are good for charging, not data, some data, not charging and some do both well.

that is the kind of cable to get. Brand name, made for charging/data, good quality.

The included charger provides 11W of power to the tablet, I'm not sure what the running consumption of the device is, but I have an acer tab the power supply of which provides 19W of power and it charges much faster. Lenovo offers a tablet dock accessory (0A33953) which includes a 65W power adapter (same that they use on many ThinkPads) and claims 8x the charging speed.

With regard to USB cables and power capacity, the USB 2.0 standard provides 2.5w (<25% of the adapter) which is likely less than the tablet consumes in standby. While cables may be capable of handling more power, they are not required to in order to get the USB logo certification. I'd suggest you look for very short cables as the longer the cable, the more important a factor the wire's resistance is to the power delivered. You can likely combine a very short cable with a higher amperage power supply to increase power output and decrease loss to resistance.

Another option, would be to use a USB 3.0 HUB which provides up to 4.5w of power per port. Newer USB devices also support the battery charging specification (http://en.wikipedia.org/wiki/USB) which shorts out the USB2/3 data ports and in exchange charges the tablet faster (up to 7.5W per port). By combining this and a usb cable that draws power from 2 ports, you can get 15W of power. I have used this type of setup to charge another tablet of mine and have managed to get 10w (2.5 from data connected line and 7.5 from power only line).

The last thing I have used in the past is the the 65w power adapter with built-in USB hub (57Y4600). I don't know what power it is outputting specifically, but it seems to charge my tablet quickly when i use it in my office.