We recently took a 2000 mile road trip, and then flew back, allowing us to run a couple of benchmarks in hotels, a Jeep, and up in the air. Even though our test vehicle was limited by its 15 A fuse, that was more than enough current for Duracell’s 175 W Pocket Inverter. We tested the charge time from 0% with wireless networking disabled, using the lowest display brightness setting, and playing back a DivX-based movie.
| Time to 100% Charge Dell Vostro 3300 HH:MM:SS | Duracell 90 W | Targus 90 W | Kensington 90 W | Stock 65 W Dell Adapter |
|---|---|---|---|---|
| From AC | - | 2:05:32 | 2:03:55 | 2:05:25 |
| From Car | - | 2:05:55 | 2:03:21 (EmPower-to-Cigarette Adapter from Duracell kit) | - |
| From Car using 175 W Duracell Inverter | - | 2:02:57 | 2:05:34 | - |
| Time to Charge from 5% to 10% Dell Vostro 3300 HH:MM:SS | Duracell 90 W | Targus 90 W | Kensington 90 W | Stock 65 W Dell Adapter |
|---|---|---|---|---|
| From AC | - | 00:5:00 | 00:04:20 | 00:04:05 |
| From Car | - | 00:05:10 | 00:04:10 (EmPower-to-Cigarette Adapter from Duracell kit) | - |
| From Car using 175 W Duracell Inverter | - | 00:05:00 | 00:04:35 | - |
| From Plane using Cigarette Plug | - | 00:05:00 | 00:04:15 (EmPower-to-Cigarette Adapter from Duracell kit) | - |
Charging times are a double-edged sword. Ideally, you want a nice slow charge so that your battery lasts more than a few hundred charges. Fast charge times keep you away from the wall socket longer. but, in the long run, they cut down on the battery's health, too. Manufacturers utilize a variety of charging schemes to strike a balance. Usually, the rate of charge starts slowing down somewhere in the 80% to 95% range, which is why the charging time from 0% to 10% is faster than 90% to 100%.
Surprisingly, there is no difference between the three adapters, at least to charge to 100%. The battery in the notebook largely regulates the trickle charge, even when it's topping off from a constant current/constant voltage charging scheme. When you look at the charge from 5-10% (the only test available on the plane, given available time), Targus' Premium Laptop Charger seems to take a more cautious approach for the faster leg of the charge.
Using the Vostro 3300, we couldn't get the Duracell charger to work. It is the only charger of the three we tested that doesn't transmit an identification signal over the center pin. As a result, you can only power a Dell-based notebook; charging is completely disabled. There is no resolution to this problem, which you might experience if you buy your adapter on Ebay for a Dell notebook. Furthermore, you can't use a power inverter in tandem with the stock power adapter, and we're not sure why.
As a result, we had to run an additional benchmark using a 13.3" MacBook Pro to test the charging time of Duracell's charger compared to the other two. We ran it at maximum brightness, wireless enabled, and a custom benchmark for web browsing that mirrors our earlier RLUMark.
| Time to 100% Charge Apple 13.3" 2010 MacBook Pro HH:MM:SS | Duracell 90 W | Targus 90 W | Kensington 90 W | Stock 60 W Apple Adapter |
|---|---|---|---|---|
| From AC | 03:00:40 | 02:53:50 | 02:55:40 | 02:55:40 |
Overall, the Duracell product is basically the same flavor of laptop charger as the other two. Aside from its price, the main differences are found in its advantages. Duracell offers a three-year warranty compared to Targus' two years and the one-year coverage from Kensington. With that said, only Targus offers "Free Tips for Life." You simply have to pay for shipping on a tip that doesn't come with the original set ($5 for UPS Ground, plus tax if you live in California).
We wanted to throw in a benchmark from a generic Ebay charger, but the one we bought off some guy in Hong Kong died two days into testing. That goes to show that you get what you pay for; buy generic power equipment and you're putting the purchase and whatever it's connected to at risk. Sounds like reason enough for us to invest in a solid adapter, if we're going to buy anything at all.
- Keeping Mobile Devices Powered-Up
- Do You Need A New Adapter?
- Hitting The Highway Or Traveling By Air
- Universal Power Adapters: How Do They Work?
- Duracell 90 W Universal AC/Auto/Air Adapter
- Targus Premium Laptop Charger (APM69US)
- Kensington Wall/Air Ultra Compact Notebook Adapter (K38067US)
- Compatibility: Will It Work?
- Which Power Adapter Is Right For You?



That seems unusual. In my house we have 3 different laptops spanning 6 year purchase dates and they all have the exact same plug. Two of the laptops are Latitudes and the other is a Studio XPS. The only difference is that the Studio XPS came with a 130 watt adapter as opposed to 65 watt adapters for the Latitudes. So no gaming with that machine while plugged into the 65 watt adapters.
Actually this sort of standard DOES exist in Europe for smart phones and cell phones, I'm not sure if it includes laptop or netbooks but it might. I'll have to search around.
It seems the bottom line today is buy the OEM adapters if you want to play it safe.
come on Toms, get the BD benchies out already.
So that $800 laptop then requires another $270 to run after 3 years? And this is assuming you don't drop the thing, or break it through normal wear and tear. And laptops do not age as gracefully as desktops because they are generally crap hardware to begin with. Much better to stick with a $300 laptop, and a decent desktop. The desktop will keep up with the times longer and will have less maintenance, while the laptop can be swapped out when need be.
Instead of buying a new Lithium-Ion batt (that would only last about another 2 years anyway), I just use a 12V 7.2Ah Lead Acid connected to the PSU input when I don't have access to a mains supply for an extended period (e.g. on long train journey).
It works cos the PSU output voltage is 15V so 12V is close enough.
cheers!
Phones and GPS devices take less current to charge than notebook batteries. These devices are moving from proprietary chargers to charging via USB. I haven't met a notebook computer yet that could charge off the low USB currents, even if the 5V supply could be pushed up to 12V.
I hope that that is so; it certainly wasn't the last time that I looked at this in detail. At that time, just putting 15V across the charging terminals of the battery and going to sleep would ruin the battery; there was all kinds of logic in the charger to protect the battery.
Have they really built this into the batter now, so that all we have to do is provide a DC source with the right voltage and no other control circuitry?