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Power Hardware

Why Is a Laptop's Battery Dearer Than a Lawnmower's? 427

Barence writes "PC Pro's contributing editor Paul Ockendon has bought a new lawnmower powered by lithium-ion batteries — part of a recent flood of such lithium-ion-powered garden and workshop tools which are taking over from NiCd and NiMH thanks to lighter weight, longer life and lack of the pernicious 'memory effect.' This is pretty much the same battery technology used in laptops, mobile phones and MP3 players, so volume manufacture is already established. Yet laptop manufacturers charge more per Watt-hour than lawnmower makers. This blog investigates whether such a seemingly ludicrous situation can be justified."
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Why Is a Laptop's Battery Dearer Than a Lawnmower's?

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  • by fooslacker ( 961470 ) on Tuesday December 15, 2009 @11:36AM (#30444634)
    Or market economics...turns out a lawnmower purchaser is not willing to pay the same for a battery that a laptop purchaser is or perhaps the lawnmower has cheaper non-lithium competitors it must compete with which drives down it's market price. I guess technically that's greed, charging what you can but without it where would we be?
  • by rAiNsT0rm ( 877553 ) on Tuesday December 15, 2009 @11:36AM (#30444642) Homepage

    Basically the only thing on newer laptops is that there is actual circuitry inside of the battery pack now, but it is all very basic and couldn't cost more than a dollar or two at best. I used to work at Radioshack in college (I know, I know, but I was actually intelligent and truly helpful... not a drone) and I once replaced the cells in my Thinkpad 600 right there on the counter with the Li cells we sold... Everyone was amazed that, that was all that was inside of there. People always seem to think because it has to do with a computer it must be magical and exotic. Basically as long as you know how to properly solder them without killing yourself (the ones with tabs help) it's a 5-10 minute job and cost about $10-15.

  • by 0x537461746943 ( 781157 ) on Tuesday December 15, 2009 @11:51AM (#30444898)
    I disagree. The cheap batteries that you can get from over seas generally don't hold up very well long term(accepting the fact that almost all LiPo batteries are actually made in China). Just go to and do some searches there for battery discharge graphs. The top of the line LiPo cells so far are ThunderPower G3 40C which have a very impressive discharge graph. They hold the same voltage as they age during load for 80% of the discharge. After 200+ flights the only thing that changes is the falloff curve at the very end which gets brought in close(less mah over 200+ cycles). I personally use Hyperion G3 35C batteries because ThunderPower doesn't make the 6s 6500mah batteries I want(only up to 5000mah). Hyperion is still very good discharge graphs but the whole discharge curve does slightly go down with age. Hyperion do a very good job of holding voltage during extreme loads like the ThunderPower. If you compare Zippy or any of the other very cheap batteries(1/3 the cost of Hyperion or ThunderPower) you will see there is a big difference between them especially after 50 cycles on them.
  • by Roberticus ( 1237374 ) on Tuesday December 15, 2009 @12:00PM (#30445036)

    Unlikely, people don't do things for the heck of it.

    Says the user posting for the heck of it, on the site created for the heck of it back in the day...

  • Re:Conratulations. (Score:5, Interesting)

    by gander666 ( 723553 ) on Tuesday December 15, 2009 @12:13PM (#30445250) Homepage
    It is called market segmentation, and in general it is good. Different segments for the same products/technologies have different values for good intrinsic to them.

    As an example, Taylor Hobson makes a fine stylus profiler. It is the standard in industry and precision manufacturing for determining shape and surface quality for parts. They charge (hypothetically) $60k for this instrument when they sell it to a manufacturer of metal precision components.

    However, the exact same instrument, with a couple of new software features is sold into the Optics production market. The price is ~ 2.5X the price of the same tool sold to the industrial market. They get this premium, because the optics production segment has a different value proposition for the measurements it makes.

    Same thing in laptop batteries. Same technology, but the application is different. Squeezing a few extra watt-hours into a smaller space is worth the premium. Also, you use you laptop much more than you use yard implements, so the perceived value of good life and longer cycles between recharging is a higher value.

    It is irrelevant that they use the same technology.
  • by IWaSBoRG ( 992305 ) on Tuesday December 15, 2009 @12:27PM (#30445474)
    Super expensive laptop batteries have always bothered me. If you've ever taken one apart you know whats inside them. A bunch of AA cells strung together in series. Thats it. They're not top of the line Energizer or Duracell either, they are the cheapest of the cheap AA lithium ion cells mass produced in china or japan or where ever is cheapest at the moment. They are worth no more than $5 in total. Its appalling how much these companies charge for trash. This isn't to say all companies use such shit. There are a few that custom make their own batteries for better performance and size.
  • Re:Conratulations. (Score:4, Interesting)

    by Maxo-Texas ( 864189 ) on Tuesday December 15, 2009 @12:46PM (#30445838)

    Part of the issue is a lack of government enforced standards since the phillips screwdriver.

    Capitalism works well when vendors can't form monopolies easily. Due to legal changes, it's become increasingly easy to form monopolies.

    Imagine if the form factor and plug type for lithium batteries was legally mandated to be 3"x1"x8" with a standard six wire plug.
    In this case, standard lithium batteries would compete based on cost and charge duration. Given standard batteries, it would be very likely that recycling and reuse programs could develop.

    Another perfect example of this is many car subsystems. You don't need 1200 Alternators and Voltage regulators. You probably need at most a dozen alternators for normal cars and trucks. If these were standardized, the cost would be lower. But we've let car makers take the same basic object and attach different custom fittings to it so it can't be reused and you must pay a premium for it.

  • Re:Conratulations. (Score:3, Interesting)

    by amorsen ( 7485 ) <> on Tuesday December 15, 2009 @01:00PM (#30446116)

    The laptop "manufacturers" actually just pay some random company to buy components and assemble them. The cell manufacturers have a much harder job, but surprisingly their margins seem much smaller.

  • Re:Not Greed .. (Score:4, Interesting)

    by idontgno ( 624372 ) on Tuesday December 15, 2009 @01:35PM (#30446792) Journal

    The designer of the laptop system selects batteries on things like power capacity and form factor/size. But since laptop batteries are, in fact, batteries of cells, the form factor can be customized. You can arrange cells within the battery casing almost at will, as long as you're willing to design the wiring appropriately, so the form factor of the battery becomes something which can be customized. (Also can be standardized, but we've already discussed that.)

    So, all things being equal, you design the battery to best match the available space among the layout of the other components in the laptop casing. And, while you're at it, coincidentally, the battery will be incompatible with laptops of other manufacturers, darn the luck.

  • Re:Conratulations. (Score:3, Interesting)

    by timeOday ( 582209 ) on Tuesday December 15, 2009 @02:00PM (#30447252)
    Most laptop battery packs still just contain cells, similar in form factor to C-cells. I don't think there are really that many different form factors of cells, it would be too much nuisance to manufacture. Most of the 1000s of battery variations, I believe, are just the packaging. Even if you take apart an electric razor, it's just AA or some other standard-sized cells. It's too bad laptop battery packs don't allow replacing cells, just like putting new D cells in your boom box.
  • Re:Not Greed .. (Score:2, Interesting)

    by DwySteve ( 521303 ) <[moc.liamg] [ta] [shciredeirfs]> on Tuesday December 15, 2009 @02:09PM (#30447402) Homepage
    Yes, all the individual cells are the same. In fact the Roomba 400 series (don't know about later ones) has an odd battery pack with an odd connector and odd screws holding it all together. When you get past the triangular slot screws and get the battery open you find... an array of 'C' size NiMH batteries wired in parallel. Which you can replace with similar batteries of equal or greater capacity (NiMH's are finicky about charging rates, Li-On and Li-Poly not as much).

    Actually, I think all of this is getting better. Battery choice was much harder back when you had NiCad or NiMH batteries which were harder to charge. If you wanted to squeeze more capacity in you had to redesign your charge circuit to some extent or make do with charging slower and/or reduced battery performance. The newer chemistries have simpler charging methods.

    But these damn laptops keep getting more powerful despite staying the same size. It's no surprise you'll have to redesign the battery pack every couple of years just to maintain performance and size. With a large garden implement you've got plenty of room to put any old battery in and leave room to spare for your aftermarket enhanced battery pack or future upgrades.

    There just aren't as many pressures affecting those batteries as there are laptop batteries. Until batteries have an excess of capacity there probably won't be standard packs. In the mean time, the gains a company gets from overdesigning the battery outweigh the costs. Especially since people will pay for smaller and longer lasting batteries.
  • Re:Not Greed .. (Score:3, Interesting)

    by yurtinus ( 1590157 ) on Tuesday December 15, 2009 @02:49PM (#30447974)
    The battery packs for tools are no more standard than those for computers; however, your battery *components* are. Your 3-cell, 4-cell, etc lithium batteries are going to be built around a standard cell. The Latitude that I have for work uses a six cell battery, 11.1 volt, 56wh. Given its dimensions and capacity, I figure it is- 6x 3.7v 18650 cells at 2500mAh (two sets of three in parallel).

    *I* can buy those batteries for roughly $24, figure cost to Dell's supplier being some fraction of that. Dell charges $150 for a replacement pack. Of course there is more to the battery than cells-- packaging and internal electronics for charging and capacity reporting, though the cost for that CCA will be less than that of the cells.

    Curious-- has anybody tried breaking open a worn out battery pack and replacing the cells?
  • by Anachragnome ( 1008495 ) on Tuesday December 15, 2009 @03:37PM (#30448688)

    Agreed. (no pun intended)

    Dell laptops do not allow a BIOS flash until after a "battery check" is performed, even if the machine is currently plugged in to a transformer/wall outlet. (take the battery out, or have a dead battery, and the BIOS flash will fail)

    There is NO reason to do this except to make sure you have a functioning battery.

    In short, they are forcing the user to buy a new battery if the old one doesn't work, even if the user never intends on unplugging the thing from the wall.

    The worst part? The "live" BIOS flash system Dell uses also allows viruses to infect the BIOS, forcing the user to re-flash if infected.

    Only reason I know this is I worked on a friends laptop, cleaned it of infections only to find out the BIOS was infected as well. When I tried to flash the BIOS, it failed with a message that explained that I needed a battery installed. It was installed, but dead. I basically had to inform my friend that he needed to buy a new battery to disinfect his machine. He opted to buy a new laptop instead. A NON-Dell.

  • Re:Conratulations. (Score:2, Interesting)

    by nazsco ( 695026 ) on Tuesday December 15, 2009 @04:08PM (#30449014) Journal

    it was true when step motors were much more expensive. Hardly the case since some 30yrs.

    Also, phillips now are used to maximize screwing by hand. which is done by using a beveled head in a edged screw. anyway, that's not the point.

    For a more on-topic note, see the screws Nintendo uses on their crap. it's a triangular phillips screwdriver. Openly used for the sole purpose of not letting kids open the damn thing.

God help those who do not help themselves. -- Wilson Mizner