back to article Happy with your Surface Pro 3's battery? Well, here's a setting that will cut the charge by half

In news that will make Surface Pro 3 owners twitch involuntarily, Microsoft is fiddling with Surface battery settings yet again. Fear not, however. The tweak is to allow users to restrict how much charge to give a battery while a Surface is plugged in. The setting, named "Enable Battery Limit Mode", and hidden within the Boot …

  1. Zippy´s Sausage Factory
    Flame

    Lenovos used to ship with software for Windows that you could set this. You know, back in the days when they made Thinkpads, not bargain bucket 32gb-drive-2gb-ram so-cheap-they're-a-ripoff plastic toys that don't even have the space for Windows Update to run...

    1. johnfbw

      Same with Sonys

      1. Dave 126 Silver badge

        Indeed, even some Xperia phones had the option to limit charging to 90%. Seems I can't do the same on my Samsung without rooting - best I can do is install an app that chirps when a certain charge level (let's go for 80%) is reached.

        For laptops, Apple, like Lenovo, were clever about charging. I've known old MacBook Pros often left plugged in that could still take a respectable charge after several years. My mid range Dell's battery died after less than a year of similar treatment.

    2. Spotswood

      Used to?

      They still do ship with this software. Running it on all my X1 Carbons.

    3. Anonymous Coward
      Anonymous Coward

      "Lenovos used to ship with software for Windows that you could set this. "

      And it is also the part where users ended up having more problems with it then without it. Putting the battery software manual on display in the bottom of a locked filing cabinet with a sign on the door saying 'Beware of the Leopard" tends to cause user more confusion when it doesn't work as intended.

      This is why it is one of the many lenovo bloatware uninstalled if the HD isn't already wiped.

      If you need to manage the battery life, you should get a laptop with a replaceable battery and unplug the battery if the laptop is going to be stationed for a long time.

      1. Anonymous Coward
        Anonymous Coward

        "If you need to manage the battery life, you should get a laptop with a replaceable battery and unplug the battery if the laptop is going to be stationed for a long time."

        That will not keep the battery good, it will need to be charged to a specific voltage to keep it good, which isn't fully charged.

    4. Anonymous Coward
      Anonymous Coward

      Still do or did do around 3 - 4 year ago I think for the yoga 2 pro, had a save battery mode for if you kept it plugged in.

      The reason is because LIPO batteries, if not used, should be charged to their nominal voltage, when under charged or fully charged they are below it or above it which damages the battery.

  2. LeahroyNake Bronze badge

    meoww

    'Redmond initially tried to extract a fee for battery replacement before eventually fixing the problem with a firmware update.'

    User replaceable battery. It's not hard. If the FW has an issue... also the manufacturer's fault / free battery for the users after they have fixed the FW.

  3. wriggyB

    "Redmond initially tried to extract a fee for battery replacement before eventually fixing the problem with a firmware update."

    Was battery replacement ever an option? - when mine bricked, less than a year ago and after trying all firmware routes, I was offered a refurb in exchange and a bill of £450 for the privilege, I presumed this was because they couldn't repair them.

    Interestingly, at the time, that refurb would likely have been a SFPro 4 and would have come with a 3 month warranty. SFPro4 had a few awful issues too.

    Given the refurb unit would almost certainly a returned unit, I decided I didn't want to double down on shonky hardware.

    Still have to slap myself whenever I longingly look at a Surface Book 2 though.

  4. Anonymous Coward
    Anonymous Coward

    Alarm avoidance - of a kind

    To avoid alarming the user, it still shows the device as fully charged and reverts back when disconnected.

    So it sits there happy as Larry, reporting charge at 100% whilst plugged in, then if unplugged goes "Just kidding! You've only got 50% juice! Bwahahahahahahahahahahaa!"

    1. Gotno iShit Wantno iShit

      Re: Alarm avoidance - of a kind

      That's the way I read it too. Really struggling to see how this is in any way good.

  5. DougS Silver badge

    I thought this was a solved problem

    Should I not be leaving my laptop plugged in for days at a time? I assumed the charge controller circuitry in the battery would let some cells discharge, then charge them up and let others discharge, to spread around the wear. Topping out at 50% charge is a really shitty solution to this issue!

    1. Waseem Alkurdi Silver badge

      Re: I thought this was a solved problem

      I do that all the time too, as my laptop-thing's battery is also the whole lower half of the bottom, which means that if the battery's out, the whole laptop would lose its center of gravity, as well as the touchpad circuitry dangling from underneath. So I thought I'd keep the damned battery in there.

      But judging from this article, this seems to be harmful practice.

      What do you think?

      Edit: Articles like this one: https://www.guidingtech.com/66018/keep-laptop-plugged-in/ assert that keeping the battery in the thing doesn't harm it. So who's correct? Them or M$?

      1. Richard 12 Silver badge

        Re: I thought this was a solved problem

        Depends on the charging algorithm and power system design.

        If the system can only be powered from the battery, with the charger continually keeping the battery fully topped off then it'll kill it.

        If it charges to full and then supplies the machine from the PSU while leaving the battery "floating" until the cell self-discharge takes it below some reasonable level, then it'll be fine.

        1. Dave 126 Silver badge

          Re: I thought this was a solved problem

          It really depends upon the make and model of laptop. Lenovo, Apple and I believe Toshiba are good, but as I noted above my mid range Dell was poor. But please, my anecdotes are half a decade out of date - lots of vendors have upped their game, so I'd suggest you spend a few minutes googling.

          With regards to what Richard has said, my Dell could run off mains with the battery removed

          1. dnicholas Bronze badge

            Re: I thought this was a solved problem

            I've got a Clevo that absolutely refuses to do anything but beep without the battery. The said battery is dead as John Cleese's parrot. Not going to buy a new one as that machine has entered semi retirement in my workshop but irks me that I can't just take it out

          2. Nate Amsden

            Re: I thought this was a solved problem

            I have a Toshiba Tecra A11 from 2010 ($1878 before accessories+support), which has probably spent greater than 99% of it's operating hours plugged in. I bought 2 extra batteries for it in the beginning, I don't recall how often I rotated them, the current battery has about 40-50% of capacity left. The other two batteries appear to be in good condition according to this tool I have called hwmonitor(https://cpuid.com/softwares/hwmonitor.html - mainly use it for looking at temperatures). Probably been 2+ years since either of them were used.

            I only say this because I thought that was "normal", didn't expect to read about batteries dieing(completely) from being plugged in too long, short of the occasional faulty battery I suppose.

            Recently rebuilt the laptop to be a gaming system for older games. Decided to keep the bad battery in it since it's hooked to a UPS anyway.

            Even on a good day when it was new, under Linux anyway and the Nvidia graphics a full charge wouldn't go much past 2 to 2.5 hours. I didn't buy it for good battery life though. One battery that is faulty on the Toshiba is the CMOS battery? If the laptop stays unplugged for too long (few days?). So even when it's turned off I keep it plugged in.

            Currently using a Lenovo P50, it spends 95%+ of it's hours stationary on my desk plugged into a fancy double conversion UPS. Battery life on this on a good day in Linux with Nvidia is maybe 3-3.5 hours.

            I replace the batteries in my main phones about once a year (Galaxy Note 3s), they spend a lot of time on wireless chargers which probably impacts the battery life. After a year they still work fine though it seems they lose 20-30% of the capacity.

      2. Dave 126 Silver badge

        Re: I thought this was a solved problem

        Lithium ion batteries last longest it cycled between 40% and 80%. They don't like heat, and they don't like being stored with less than 40% charge. There was a clear Reg article about this a few years back.

        With regards to laptops, it's clear that the premium brands* have traditionally fared far, far better than budget brands/ranges - likely due to better control circuitry and balancing of binned li-ion cells.

        *The ones who consistently top studies of reliability composed using multiple data sources.

  6. Anonymous Coward Silver badge
    Boffin

    But

    Surely if a device spends all of its life plugged in, the user doesn't really care what the battery life is like.

    If they charge the device and then use it until it's flat, then charge and repeat... they probably do care and the battery is being conditioned too.

    So where is the problem?

    1. Dave 126 Silver badge

      Just no

      It's not uncommon for people to use a laptop as they would a desktop, plugged in on their home desk for most of the week. That shouldn't preclude them from having a working battery for the odd occasion they want to use their laptop away from a power socket for a few hours.

      Oh, and by the way, the Deep Cycling you describe (run til flat, charge to full, repeat) does NOT 'condition' Li Ion batteries - it actually degrades them, and quickly. Li Ion likes being cycled between roughly 40 and 80% charge, and doesn't mind short periods of topping up. The cycling you describe is for Nickel Cadmium batteries, but these are rarely used these days (possibly in cheaper electric toothbrushes).

      1. Richard 12 Silver badge

        Re: Just no

        Ni-Cads are only used in specialist applications these days, as cadmium is very nasty stuff and they're much harder to charge to full without damage.

        They can however produce ludicrous current from very small cells, and don't catch fire when they burst (unlike lithium-based cells) so are very useful in some situations.

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