Windows Phone Thoughts: Portable Power with Proporta's Laptop Battery

Sufficient Power? That Depends…
The 6000 mAH battery is sufficient to power a variety of devices, but this will vary widely based on the type of laptop you're connecting it to. For instance, my Fujitsu P7010D is a small laptop with a 10.6" screen and a 4800 mAH primary battery that gave me around six hours of run time when it was brand new (it's down to about five hours now). An electrical engineer could explain this better than I can, but there's always efficiency lost when one battery charges another. As a test, I ran my 4800 mAH battery completely flat, and then connected the 6000 mAH Proporta Laptop Battery to it. I was expecting it to recharge the 4800 mAH battery and have some juice left over (1200 mAH) to recharge a device or two. After several hours I found that my Fujitsu laptop was back up to 100% power, but the Proporta battery was completely dead – with nary a mAH left to recharge anything else. My crude method of measurement (and I use that term loosely) gives us about 20% lost power, making the Proporta battery 80% efficient. I have no idea how that compares to other products of this type on the market, but it's something to be aware of.

Realistically, most people are going to use the Proporta battery to top-up a partially depleted laptop battery, or use it as a primary power source until depleted then switch over to their laptop battery. My testing method is a worst-case emergency scenario. On the plus side, I was away for a six days and used it to recharge my HTC Touch from 50% power three times and it only used one pip of power. You can finally leave behind the AC power bricks for all your USB devices – assuming they charge via USB that is (curse you Motorola for putting a miniUSB connector on my wife's KRZR but not letting it recharge without your "special" AC power adaptor).


Figure 5: There's my Zune (Colorware customized and pathetically fragile now because of it) getting juiced by the Proporta Laptop Battery.

So what does this mean to you then? If you have a laptop with a battery around 5000 mAH, the Proporta Laptop Battery will give you one full recharge – but leave nothing for any of your other USB-based devices. This flies in the face of their product page which claims "recharge your laptop for prolonged use or several emergency charges" – perhaps several partial charges, but certainly not full charges unless the laptop has an anemic 2000 mAH battery. If you have a laptop such as mine with a primary (4800 mAH) and secondary battery (2300 mAH), the Proporta battery won't even be able to provide one full charge. When I recharged my laptop with both batteries in, I got about 75% charges on each battery (16% power efficiency loss, which is about right). Given that I can get around 10 hours of run time with both batteries in my laptop, that means with the Proporta battery connected I could get around 17 hours – enough for all but the longest of flights.

Postlude Ponderings
If it sounds like I'm not a fan of this product, that's not the case at all – while I wish Proporta would release something with slightly bigger capacity (say, 8000 mAH), the current product is so nicely designed that I wouldn't want to travel without it. The ability to recharge a variety of devices via USB is absolutely fantastic – and despite what the Proporta product page says, my Microsoft Zune charges just fine, as long as I use the official Zune USB cable. The combination of a sub-$200 price with tips for an assortment of laptops makes this a much better deal than something like the Valence N-Charge which has a higher base price and the added restriction of requiring a $50 accessory for every type of laptop you want to connect (and no USB port – I practically begged them to add one when I reviewed it in 2006). I see no reason to carry my N-Charge any longer, especially as I'm switching laptops (from my Fujitsu P7010D to a Dell XPS M1330 - if the damn thing ever ships!) and I have everything I need already included with the Proporta Laptop Battery. This is a highly useful, functional product that does exactly what it's supposed to do.

Jason Dunn owns and operates Thoughts Media Inc., a company dedicated to creating the best in online enthusiast communities. He enjoys mobile devices, digital media content creation/editing, and pretty much all technology. He lives in Calgary, Alberta, Canada with his lovely wife, and his mostly obedient dog. He's obsessed with battery life. Can you tell?