How's this for an idea for laptop batteries?

I've always thought having two laptop batteries would be a pain to maintain mainly because you have to have the battery in the laptop in order to charge it. Sure sometimes you can find an external device but they cost $50-$100 or more, but you can't always find them for all models either.

Why don't battery manufacturer's start putting a mini-USB port in every battery so you can charge it from your laptop while plugged in? Or from a wall outlet adapter? Then you'd just need a USB to mini USB cable to charge a battery. Pretty standard part.

I don't really see any downsides to this other than a little extra cost for each battery, but it can't be that much because you can buy a $10 MP3 player that has the same technology integrated. As a customer I'd rather pay a few bucks extra for every battery to have that feature than spend money for a proprietary adapter.

 

Why?

Because a USB port is only rated for 2.5W - your second battery might be charged in a month...

 

It might take 24 hours for a fully drained battery, even less with USB 3.0 (4.5W). But at least it would be an option. Many people don't need a second battery on a daily basis. Or use a two USB port to one mini USB for faster charging. I dunno, but it'd be easier and better IMHO than swapping your battery all the time just to charge one up.

 

I was j/k about the month part, the 2.5W is real though. The USB port would need to output a higher voltage than your battery's nominal charge is and then, it would need to deliver the amperage that would entail.

What you're asking for is impossible unless the entire charging cicuit becomes part of the battery - a much more expensive proposition than simply swapping batteries - and it would still take forever to charge fully (although, this would arguably be the best 'trickle' charge ever).

How long would it take to charge? Well, my 84WHr battery would take at least 84/2.5=33.6 hrs with a 100% effecient charging setup. At the more common 70% effeciency it would take closer to 48 hrs.

Can you begin to see that with the added cost of the inverter/controller/charger on each battery, the additional stress on the USB port(s) (and the added cost to 'guarantee' such ports), and the slow/ineffective recharge times for the second battery, why this idea has not been pursued?

 

DC/DC converters are very inefficient, normally we go for DC/AC/DC, meaning your maximum efficiency is already ~85% from the converters. You're then looking at 2W. Added to that, the battery has internal resistance generated from circuitry that consist of diodes, meaning your losing 0.3-0.7V per diode. The feasability of driving such a small current though semiconductors may mean they act like insulators. Adding this on to tiller's arguments, you may be having 60 hour charge times.

I suggest, we make the battery with several USB port, say 4 USB ports! That will mean we'll have 10W, reducing it to round about 15 hour charge times.

 

Lol...

Fishsticks, with current platforms that support 12 USB ports (and soon 16 USB ports), we could charge that battery even faster - can you imagine a notebook with 12+ USB ports all the way around? Lol...

Some ideas are worth pursuing Fishsticks (and htwingnut, please don't take this the wrong way - there are no wrong questions!), but your response (fish) made my day.

Started seeing Tim the Tool man Taylor using a gas power Honda motor to make sure those USB ports were 'man enough' to charge the attached battery...

lol...

 

fishsticks

I am not sure where your coming from but your other argument in the battery leave forum and now this makes me (with face in palm) say stop, just stop.

While the original OP has an idea it just is not feasible, the problem is you have to step up the voltage to values that range in the 16-20 volts. If you step up voltage you have to step down the current, since that would be a 3.5 X boost the maximum current out would be less than 1/3 of 500ma or 150 ma. It would take a long time to charge at that rate.

 

Awww, tiddlywinks. I didn't think it through very much, but it just ran through my head like a derelict mouse caught on a treadmill racing for that piece of cheese on a string.... story of my life.

 

Problem:

Solution:

Conclusion:

hahahhahah

 

Wish I was good at Photoshop, I would get a pic of four laptops with 3 usb cables going to this contraption that is twice the size of the batteries, all plugged into a power strip that is way overloaded with everything in the house. It would be classic.

anyway.......

 

Ahahahah, I just got the funniest idea!
How much power can we draw through the ExpressCard slot?

 

Hahaahahahaha... stick your tongue/finger in and find out!


















No, Don't JOKING!

 

With all kidding aside, if you take the OP’s original idea and say instead of the USB ports providing power, you allow a power supply to provide power the electrical problem is eliminated.

The problem then becomes mechanical, you would need to develop a universal cradle that would accept a large number of battery adapters that you would plug the batteries into.

Now the cost to research and develop would lie in the mechanicals and the molds, not the electrical.

In the end I do not think the market is big enough for a company to spend that kind of money on development of such a system.

 

Guys, a little bit out of topic here. Does anyone know whether using a "Disable Battery Charging" option in Battery Meter has the same effect as taking out the battery physically?

I always use ac power all the time and as being said everywhere on how to prolong battery life, my battery is always charged to around 40% every 1-2 months and then store it safe, and repeat... Kinda get bored now...

 

No it doesn't. Part of the wear on the battery comes from heat exposure than charge exposure. If it's still in the laptop, it's still going to to get warm and lose some capacity.


As for the main topic, I want universal bays to become commonplace - you used to be able to swap an optical drive/harddrive/batteries on a whim.

 

USB charging a battery for a laptop is not feasible. Or possible.
Yes there are platforms that carry 12 usb's, however have you forgotten those laptops have a max wattage input of 95w-130w. Meaning 12 usb's running at full rated power (2.5w, which is [email protected]) would produce a whopping 30w of output power (over only 5 meters of cable) which if I am correct would push any power adapter supplied with your manufacturer past it's limits/burn/stop working.
Of course there's no 12 usb laptops, I doubt their motherboards could handle that type of power.. The most I have seen was 6 USB's on a business class HP laptop..

How about we look to wireless power instead? Something Nikola Tesla was experimenting with before we were born.

 

Just seems like there's gotta be a better way. That's what I'm talking about is proprietary connectors. Seems like there'd be a much better and easier and cheaper way to recharge your batteries outside the laptop. Even a standard power adapter you just plug into the wall and then into the battery. If every battery had the same adapter in it, then you would have options, but as it stands you need a specific charger to match up to the battery's connector.

 

How to prolong lithium-based batteries

Temperature and both high charge levels are both factors in battery decay. With temperature of course being the most profound of the two factors.

 

Crimson

Your leading this topic right into this thread: http://forum.notebookreview.com/hardware-components-aftermarket-upgrades/513783-battery-leave.html

 

this would not be practical unless u have 10 USB3.0 ports... and most probably u would burn out the ports in the laptop..