Scott Hanselman

Review - Mophie Juice Pack (not the Juice Pack Air)

July 03, 2009 Comment on this post [8] Posted in Reviews
Sponsored By

The battery life on my iPhone is laughable. If I want to actually use it, like make use of it, then it's dead by after lunch. With 3G, Wi-Fi, Bluetooth, GPS, work and personal mail, yada yada, it's a joke.

Here's a picture of me with my first external battery pack. This got me through the day, but it wasn't very convenient.

When the Mophie Juice Pack Air was announced, I was thrilled. Over the moon. A battery pack that was also a case? Sleek and doubled your battery life? Brilliant.

I ordered one immediately on Amazon. When it showed up, I learned that there's actually a "Juice Pack" and the "Juice Pack Air." This distinction had escaped me...turns out I ordered the original Juice Pack, rather than the more sleek and form-fitting Juice Pack Air.

I did some research, and found out that there's basically three differences between the Juice Pack and Juice Pack Air.

Juice Pack Juice Pack Air
Chunky and only covers 7/8ths of the back of the phone. Sleek and covers the entire phone.
1800 mAh 1200 mAh
Always on (always trying to charge) On/Off switch lets you decide when it's charging

I liked the slim idea of the Air, but I figured 50% more mAh was better for me as a power-user, so I stuck with the standard Mophie Juice Pack, not the Air.

Now, let me say, I really want to like the Mophie Juice Pack. Truly. I hate being negative because I realize there's a company and actual humans behind this product.  However, it just doesn't live up to real world usage.


I've had the Juice Pack for just about 60 days. I don't work in construction and I don't throw my phone around. Still, the surface of the Juice Pack is rubbing away in a really unattractive way.

See the picture at right? The shiny patches on the corners are where it's wearing away. This is after 2 months.

The sides of the pack have, for some reason, (perhaps grippy-ness?) rubber strips about 2 inches long. On both sides it's wearing away. On the one side it's sliding off and the adhesive/glue stuff is showing. It's very frustrating to see such poor construction around my little phone Star Trek Data Pad.

Charging Behavior

I use the pack all day and so far, it DOES get me through the day, from 8 am to about 6pm before I need to start worrying. I have the brightness of the phone at 30%, Wi Fi on, Bluetooth on, GPS off. I figured with 1800 mAh would get me 12+ hours of normal usage, as the specifications talk about numbers like 28 hours of audio playback and 12 hours of 2G (Edge) talk time, but still, 10 hours is not bad.

The Mophie Juice Pack has 4 small LEDs on the back that tell you how much charge the pack has left. The features page says it has "Smart Battery Technology [that] instructs the iPhone to always drain out the juice pack first." As a technologist, I think this statement isn't really fair, as the iPhone thinks it's plugged-in when the batter is attached. When the "plug power" (in this case, the battery) stops, then the iPhone's battery stars. This is the same behavior as my old $10 4 AA battery charger.

The Juice Pack doesn't have an on-off switch, so it tries to charge the iPhone immediately, even if it doesn't need it, which appears to use power. For me, this means that the Juice Pack's battery is dead for me by around 1pm, which means I'm on my own by the early afternoon. I'd prefer to have the opposite behavior, which is enabled by the switch on the Juice Pack Air. I'd like to drain the iPhone's own battery first, then have the Juice Pack kick in.

Weird Behavior

A nice feature of the battery is that the charging cable is a standard mini-USB, which is more standard than the iPhone cable. However, one oddity is that sometimes I'll have the phone inside the battery and a charging cable attached to the battery and both are discharging. I'd expect the battery to always charge when plugged in. In these cases I have to separate the battery from the phone in order to charge the former. It's odd, as it's caused me to end up with a dead phone battery even while the external one was plugged in, just not charging.

Power Drop Off

After only 2 months, even though I discharge the battery fully (via normal use) every day, and charge it overnight, its lifetime had dropped already. This is after about 60 full cycles. When the battery light indicator reaches 2 out of 4 LEDs, it drops off dramatically within an hour. Basically 4 LEDs to 2 LEDs is 3 hours and 2 LEDs to 1 LED is an hour. This is anecdotal, to be sure, but it's everyday and it's dramatic to the point of pissing me off.

Unreasonable Expectations? Maybe.

The specs say 350 hours of standby?  I can't see how, unless EVERYTHING is turned off...perhaps 350 hours of airplane mode. I'd like a single 18 hour day of normal usage. Or, even a reliable 12.

It's so bad that I have purchased car chargers for both cars and I'm forced to top-up at least once, sometimes twice a day.

It was US$100, which is a lot for anything, including a battery. It's now ugly after two months and at this rate, I'll  be surprised if the charge lasts the rest of the year.

If you have this battery, leave a comment here. Did I get a dud? We'll see and I'll keep this review updated.

About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

facebook twitter subscribe
About   Newsletter
Hosting By
Hosted in an Azure App Service
July 03, 2009 14:37
<iphone rant>
apple really are the kings of marketing.. yes. the iphone has a decent, even great, ui, but other than that.. i just imagine if microsoft would have released it instead, people would have flamed it back to the stone age.. there could have been to many class action/antitrust suits to count.. but when apple does it? sure..
</iphone rant>

i'll never buy an iphone or a pre for that matter. i'll wait for the asus eepc with multitouch and use skype and a BT headset :)
July 03, 2009 16:41
Which iPhone are we talking about? The 3G or the 3G S? I heard that the 3G S has improved battery life but without having used either I have no way of knowing for sure. I've gotten spoiled with my Blackberry Curve - BB's have always had outstanding battery life. It's nice not to constantly have your phone tethered to a charger when you're not using it.
July 03, 2009 16:57
I have used the Kensington Mini Battery Charger and it is pretty good, others have good experiance as well (

July 03, 2009 17:51
I have the JuicePack also, and I have been less than impressed. First, the form factor gives me the feeling that I am carrying a smallish brick in my pocket. The USB cable means that if I want to listen to the iPhone in the car, I have to take the JuicePack off. That's a bit annoying. I know that they didn't have much of a choice as a pass-through iPhone connection would add a solid inch to the bottom of the phone.

On the charge/discharge behavior, I agree with you.

My main use for it now is on long bike rides, when I use a GPS tracker that's always on.
July 04, 2009 8:42
I dunno, man. I think there must be some wild fluctuations in battery quality. My first generation iPhone would routinely go three days without a charge (granted, I had e-mail checking off, since I don't act on e-mail unless I intend to check it). My new 3GS goes two days without issue.

Another disclaimer... I never have Bluetooth on. Heck, I never have it on my laptop either unless I'm using a mouse. I think it's wise to turn off radios you're not using.
July 07, 2009 9:37
I own the Juice Pack Air, originally used with my 3G and now the 3GS. It has been fantastic with the 3G. The case is nice, fits well, love the on/off switch and it really extends the battery life. I've not experienced any negative aspects with this product in using with my 3G. Prior to ordering I read the reviews on Amazon of the original Juice Pack - many users complained of the same issues you've cited Scott. So unfortunately, I'm not surprised. They struck me as inherent to the unit's design.

Bottom line, I'd recommend the Juice Pack Air without a doubt for your 3G. I *think* I can say the same for the 3GS - and here is the but....

But, I've received an odd message just a few times on the 3GS the unit is not compatible for charging. Again, only a few times but it has happened - not sure why and personally I think this is Apple's issue not Mophie. Secondly, the iPhone 3GS seems to get a bit hot. Again, probably not fair to push this on Mophie as I read in the Apple forums of hot 3GS models. Aside from that it's been great with the 3GS as well.
July 21, 2009 3:34
With any lithium-ion based battery, draining it is actually *bad* for use. Lithium-ion batteries (as opposed to their older nickel-cadmium-based bretheren), last longer if you charge them frequently, and before you drain it too much. Check out the wikipedia article:

As you can see in the article, heat plays into it as well. My wife always leaves her laptop open and on our bed, and plugged in, and after 2 years of that (on a 3 year old laptop), it can't hold a charge for longer than 60 seconds or so.

Comments are closed.

Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.