using an external battery to extend laptop/netbook life

There are a variety of third-party battery products out there claiming to significantly extend the life of laptops or netbook on the go. For example: Battery Geek Inc. - External Li-ion Battery Packs

Are they worth the money? I'm suspicious that they cost too much for the extra life that they actually provide.

I briefly toyed with the idea of buying an m11x and one of these batteries to squeeze out more unplugged gaming time, but that would just be a solution too easy to be true and probably give me only a few extra minutes.

 

go to BatterySpace.com/AA Portable Power Corp. Tel: 510-525-2328 - Powerizer Battery Official Site Build your own ^^ It's easy and batteryspace has a forum filled with DIYs. Also if you post your own DIY on their forums they give you a giftcard for your next purchase ^^....i think they still do that

 

This.

It is expensive to build batteries that can hold a lot of capacity, that also can discharge enough current to feed a power-hungry unit like a laptop, and does not weigh a ton.

For most laptops, it's more efficient to buy a spare battery. For the Alienware M11x (which does not have a spare battery), I say just live with the battery life you have, or perhaps get a smaller and lighter charger that works in AC / auto / air. I don't think it's worth getting an external battery.

 

Wrong...theirs are just over priced! The link i gave him has cells for 9 bucks a piece.
Note That these batteries are different voltages
Also they are the same capcity but they are different sizes and different amount of recharges. If you do not care about size go with the LiFePO4 battery becuase it has 6 times more charge cycles. You should get 2000 charges out of it.


This is a regular Li-ion battery cell. it has 9.62 Wh. This is smaller and denser than the LiFePO4 battery but has less recharges. Only 300 charges til it's at 80% of capacity. Also this is the cell you use to rebuild your battery when it gets old.
3.7v 18650
Li-ion 18650 Cylindrical Rechargeable Cell: 3.7V 2600mAh (9.62Wh) --OEM from Japan/Korea



This is LiFePO4 battery cell. It has 10Wh but is larger than the 18650 cells. It has a lower density but has over 2k charges at 0C til it hits 80% capcity.
3.2v 26650
LiFePO4 26650 Rechargeable Cell: 3.2V 3300 mAh, 16.5A Rate, 10Wh - UN approved (NDGR)




So you can build a 200Wh for about 180 bucks. That is 20 cells total, which is more than 3 times the storage of a hi-capacity 6 cell battery....oh it'll be a bit more because of shipping and adapters and charger. But still way cheaper than 400 bucks. Again if you do not need to worry about size use the LiFePO4 batteries because you could drain that every day for more than 5 years and still have 80% capacity. Ideal for home back ups until nanowire batteries come out ^^

 

$180 isn't a lot of money to you?

I don't know about you, but I'd rather have $180 in my pocket than longer battery life. But to each his own.

 

That site was selling 200Wh batteries for 400 bucks.....400 or 200? big differance. Also how much does a 6 cell battey cost? You can rebuild yours for like 50 bucks....alot cheaper than 80-130...depending on how stupid they are with prices.

 

Sorry I honestly don't trust non-OEM/non-manufacturer batteries. Too many times I see them fry motherboards.

Case in point, a customer bought a 3rd party battery less than 2 weeks and the notebook was no longer detecting and charging it. To deal with that kinda hassle and RMA process, no thanks.

 

these batteries are of good quality and these you build ur own packs....these aren't 3rd party batteries like ur thinking. Your solely buying the cells and rebuilding the pack.


talks about the PCM/PCB and BMS
http://www.batteryspace.com/pcbbmscmbfordiy.aspx

 

DCMAKER

In several posts we have discussed these projects of building a battery backup or some kind of replacement system, have you built any of them yet? I am curious as you always make it sound simple and cheap. The reason I ask is there are always things that come up that were not taken into consideration that will put a wrench in the spokes of what seemingly was at one time a simple project. Let us know.

Also one area of cost you don’t talk about is someone’s time. I for one consider my time quite valuable. If I spent even an hour of time on something like this, I now need to consider whether it makes sense to just buy a second battery or as in the one post a pre-built battery backup with built in inverter, versus going to all that trouble to build my own.

Something to ponder

 

I get what you’re saying. I have only rebuilt a battery once before but i have been running through their forums on DIY examples. Down the road I’ll rebuild my drill battery too....that one looks really easy ^^ And yes i don't count time in because my time costs nothing lol....i don't make squat so I would always rebuild since its easy to do this on the phone or watching TV ^^ But yea if you make a lot of money than...obviously don't bother. If you like building things and getting dirty thats a different story ^^. Oh and my time is very valuable...but when you equate how much I make a year with how much I save it's well worth it for me ^^ Though I can see making larger battery backups a bit more tricky and challenging since you need to work with more cells and wires and make your own holder. Rebuilding a laptop battery is simple but I do get your point.

EDIT: also if he is going to build a back up in the 200+Wh range than DIY is way better....its like 400 bucks on that site ^^

Also if you build it to put out the same power as your psu you wont need an inverter but that will limit the battery to just devices of that voltage. So if you got a 19.2v psu you cna build a backup with 19.2v and than you can connect it directly without using an inverter...save money and energy. You got to consider that using a convert is going to loose anywhere form 10-30% power and than on top of that your psu is going to loose 10-30% power depending on the quality. so that will make you loose 20-60% of your battery back up in just the conversion process....a large waste when your battery puts out the DC power you need. Going to DC-AC-DC is pointless if you build ur back up to your device. Though I do not know about how much variation can go into voltage. For an example, if you got a 19.2v psu can your battery put out 20v and still work or does it have to be with in .5v of your rated psu? Thats something I do not know and I really would like to know :/

 

Actually nothing to ponder really: If you're a pro with all the proper equipment, build it yourself. For the other 99% of us, buying a battery from well known supplier (i.e. your laptop manufacturer) is the best way to go. To suggest otherwise, to a general audience is just bad advice.

Even under the pristine conditions li-ion batteries can develop issue. These are not something you want to worry about or take a chance on with in your valuable computer.

Incidentally, if you're planning on purchasing a laptop for the holidays, a spare battery might be something to consider. They're typically much cheaper when you order them at the time of purchase.

 

I disagree I am about as retarded as it comes and I learned how to do it by using common sense and looking at other DIY's. There are hundreds of DIY's on their forums. It honestly isn't that hard...I think soldering is harder...I refuse to do that because I lack all sense of coordination

 

Krane:

I am not sure why you chimed in on a post directed at someone else. But me and DCMAKER have had several posts where he had an idea for some kind of battery backup devices and I have tried to play the devils advocate on some of the posts to discourage the types of home made projects he was proposing. I do know that DCMAKER is using the internet how to’s to get his information and while they are informative and not totally off the mark, they are not able to help in situations where things are not going as described. I am one of the 1% you describe, I have over 20 years of professional engineering experience in designing battery systems that include custom batteries and chargers. I was asking if he had infact built one of the concepts he had to see how it went.

Also my comment about the values of one time is another point to consider (again being devils advocate) when doing something like this. Personally based on my knowledge of this kind of stuff and the value of my time, it makes so much more sense to buy a new battery pack or buy a battery backup system that is already to go, then trying to save a few bucks. (That you may not end up saving in the end).

It's just safer, and more reliable to buy something that has already been properly designed and manufactured

PS: DCMAKER, never ever solder onto batteries, it will damage them no matter how quick or careful you try to be.

 

Good point. Plus I can't imagine if something goes wrong batteries explode? Plus you get warranties with batteries, rather than you building it yourself.

 

when I said that I wasn't referring to soldering the battery itself....I was talking about the DC wire from the pack to the appropriate adapter


here is what i am talking about

EDIT:honestly people's constant fear of Li-ion exploding is ridiculous. They are not that dangereous. Also LiFePO4 are not explosive.


EDIT: Also When i made that comment i was going from what I have seen/learn from my razr battery pack. From what I learned from it's protective layer falling appart is the design i drew. It appears to have that tpye of design...now this is some what speclative because i never fully took it apart.

On a sidenote. Those external batteries are really nice...just over priced. I mean they look nice and good...can't say more than that unless I see them. Buy me one and i'll review it ^^ my power goes out on base all the time ^^

http://www.batteryspace.com/lifepo4cellspacks.aspx
http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery

 

I have been on batteryspace several times myself. I was looking for an inexpensive why to charge our custom battery pack for production. This pack is a 6 cell 4/5A NiMH pack. We ordered one of those cheap RC battery chargers, and frankly they are okay for hobbiest use, but they are in no way good enough for professional use where I have to verify the unit is working as intended and perform a process validation that it works in a repeatable fashion. (which it is not)

 

True but it is very rare as long as you’re not stupid with it. Also the LiFePO4 can't explode. They are made of non explosive material

 

Sorry to double post but this was kinda important. Batteries you buy on batteryspace can be UN approved or non UN approved. UN approved batteries go through a lot of testing to make sure they are safe.

Most LiFePO4 batteries are UN approved. It will state it in the title of the battery.


Most li-ion batteries are not UN approved but some are.


UN Test 38.3 (PDF file explaining the order)
http://www.phmsa.dot.gov/staticfile..._Test_Manual_Lithium_Battery_Requirements.pdf