D800 dual battery

Question

Hello all   I have a D800, windows xp pro and a spare battery in the bay. my question is: i noticed that my d800 uses only 1 battery at a time. when 1 battery is low i got a low power warning despite the other battery full charged. how do you configure either windows or the d800 to use both batteries?

joegrant · Answer

Hi,

I am too having this 'problem'. The secondary battery starts the drain first, however I noticed that once it reaches the warning level, I get the warning. Then, after the shutdown threshold level is met, the PC will shut down. However, the weird thing is that the primary battery is charged up all the way.

Is there a seamless way to make the battery switch with out having to go into hybernate mode?

DELL, please let us know...

regards,

joe

Manh · Answer

Unlike hard drives, batteries are not 'arrays'.  You can't simply tell Windows to use ALL power sources at once.  Laptops were never designed this way.  It drains one battery, then the next, etc..  The batteries are not connected in series like 4 'AA' batteries in a toy, so there really isn't a way to draw power simultaneous from all available power sources.  Therefore the functionality you are experiencing is by design (and limitations) of laptops, not just @ Dell.   The power is 'supposed' to recognize the battery is available, so when it gets low it will automatically switch to the battery with available power.

joegrant · Answer

Thank you very much for the reply.    I'm cool with what you explained; it makes perfect sence.  However, the part that throws me off is the statement about 'the power is 'supposed' to recognize the battery is available, so when it gets low it will automatically switch to the battery with available power.'.  In my case, there is no 'switching' going on.    It seems that when power is drained one has to manually change the battery.  No real biggie, I just thought this is something that would get done automatically by the OS.  Is there some software setting to enable this?  Perhaps in the registry?   joe

ctlotus · Answer

Hi Joegrant,

I have the exact same Problem! Dell do not seem to have done anything about this in a while!

I personally think that what Manh is saying stacks up to not a lot!

If you read through the readme for the Dell BIOS for the D800, there are several reference to them altering the algorythm that controls the charging and more importantly the dis-charging of the batteries.

From what It says, they modified the BIOS so that it will discharge the media bay battery to 3% remaining first and SHOULD then move to the main battery, discharging this to 3% too. It will then go back to the media bay battery and drian it to 0% before doing the same with the main battery.

This process should be SEEMLESS!!! I have numerous Dell Latitudes including C and D series machines. with 2 batteries in the bays on a C series machine the Hibernation between batteries never happens!

Funnily enough I have just read in another post that someone is having the same problem with a D600. As one of my guys has one of those, I will be asking him to try it and see if he has the same results!

I would suggest DELL need to get their finger out and fix this problem!

My conclusion... it has to be a BIOS thing.

Unless it is XP SP2 but I would imagine everyone would have the problem then and it would be much more widespread!

Comments??... From Dell would be nice!

CT

joegrant · Answer

Well, I agree with you.

I have been reading this forum, and so far I find Dell not very responsive. THey don't answer questions in depth enough and many times, they just simply ignore questions. I am frankly dissapointed.

You figure when one pays the kind of $$ that a D800 fully loaded has, Dell would be more receptive to answering questions in a clear way...

oh well, maybe they will answer our question... I know there seems to be quite a few folks asking the same thing...

ctlotus · Answer

Thanks,

For what it's wirth I have lodged a suport e-mail with Dell and I have just received a response. Completely useless. I have figured out more about the problem in the forum than Tech Support has provided.

I have also found a couple of other threads where people have the same situation as us. The general concensus seems to be to change the battery warning to below the 3% battery switchover point.

I have set mine to 2% and 1% respectively.

I will test it out today and see what happens.

Watch this space...

ctlotus · Answer

Hi All,

Just an update on my progress so far...

I have followed several suggestions from the e-mails I have received from Dell Tech Support. None have been successful!

Not saying it doesn't work for others, but the 2% & 1% settings in the power management made absolutley no difference to my machine at all.

I'll update you further if I get anywhere with Tech Support.

CT.

Manh · Answer

Joegrant, you are aware this isn't a support forum, its a SELF HELP forum.  Dell does not monitor this web site.  You need to CALL them for support.  This forum is here to field support from OTHER USERS.

Manh · Answer

Obviously, you didn't heed my warning.. and from an earlier comment you surmise I am some first year computer student.  Let me say this again.. Its a design flaw by motherboard manfacturers, and by battery manufactures.  You can read, post, dig, and try to research until you are blue in the face, but what it amounts to is this is simply not a function that a very small number of people use.. maybe even smaller now since batteries have a much higher capacity, and are better quality.   The power is 'supposed' to recognize the battery is available, so when it gets low it will automatically switch to the battery with available power.   The 'supposed', is obvious to most, but evidently I assumed it was apparent, so it means the specifications call for the battery to tell the hardware motherboard (which Dell does not make, that's Intel) to switch over to another power source.. Its not happening.  Intel doesn't care, nor will they ever fix the problem.  Sony, Hitachi, Toshiba, Compaq, Gateway, and IBM *ALL* have the same identical problem.. Batteries are not smart like a hard drive, they don't report errors.. or problems.  So what you end up with is what you got, zip.  Its not working, and if you keep trying to get it fixed you only waste your time.  Get a larger battery, decrease the power on your laptop, or get an external battery.. APC makes one just for laptops.. 6 hours.. of use.  That's what you need to do.   I have only been working on these types of issues for 15 years now, I think I may know a thing or two..  So don't be so quick to dictate that 'amounts to a whole lot of nothing' is the information, it may be your limited understanding of the technology.   Yes, you have 2 batteries, no its not working like it should.  It should, but since you are probably less than 1% of people that actually use 2 batteries.. rather than just simply swap them out.. you won't get any assistance with this problem.   Call a battery manfacturer, tell them they need to make a system like a hard drive to communicate with the system so that it will accurately feed back the status.. lets see how far YOU get.  A battery is a chemical, its imbalanced.. hardware has to take readings on an aggragrate scale just to get figure out what the battery level is.. That's where the crux of the problem is.. Batteries are simply innefficient, write your congressman..

ctlotus · Answer

Manh,

Why are you getting so wound up? If this is what you think then so be it. The rest of us are interested in trying to resolve the problem. Quit being so obstructive. You obviously didn't read my earlier post... I have numerous machines that do not do this. It is only the newer D series machines that have these symptoms.

To be honest, your ranting does not really deserve a reply, but I feel you need to be set straight on a few things which do seem to make you come across like a first year computer student. And which the rest of us in this thread are taking for granted and interested in hearing the answer to. If you have nothing constuctive to add then why add at all? Quit trying to be-little those of us happy to pool the little bits of information we each have and try to build a bigger picture.

If the machine cannot switch batteries when dis-charging, how come it can manage it when charging? You don't have to power-cycle the machine to charge the 2nd battery when the first has reached 100%.

Intel do not manufacture the MoBo's. The chips contained on the motherboards and the architecture are designed by Intel. The actual manufacturer of the boards varies from one PC manufacturer to another.

I think you would be surprised at the number of users who run their laptops on 2 batteries. Why manufacture and sell them unless there is demand? Do you think Dell makes these products without talking to it's major customers to see what they require from new models? I think not!

You may have been working with these issues for 15 years but I would suggest you have become flippant and write things off without thinking through the theory of what you write.

Batteries ARE smart! Thats why they are called Smart LIon. What do you think the smart stands for? Why do you think when you place a battery into a laptop, the machine instantly knows the current charge level in the battery? for that matter, how do you think when you look at the battery meter application, it can tell you the manufacturer and chemistry of the battery? Hmmm... more porely thought through conjecture.

Thanks for the science lesson by the way... I never realised that Lithium was a chemical. Blimey!

Just one final question... If the battery is so basic, how come there are so many connecting terminals? If it was as simple as charge and dis-charge, surely all it would need would be the + and - terminals?

I would suggest the information spewing from your keyboard is as outdated as the time you have been dealing with these issues!

Please allow this post to be used for the purpose it was put here: to help those of us interested in a solution.

CT

ctlotus · Answer

Hi All,

Just another quick update,

Without wanting to sound smug, I have just received an e-mail from Dell to tell me that there is a new BIOS version out for the D800, A12.

One of the items fixed in this new version is the problem we have been suffering from! I have installed the update and I'm now charging both batteries up!

If you haven't done this before, just remember to make sure you have the mains power connected and for the best reliability, install the update in DOS and not Windows. You can do this with a Bootable USB key or a Floppy Disk.

I'll post again once I have the results.

CT.

joegrant · Answer

ALLRIGHT!!! I'll see if I can get a copy of the BIOS. Thank you sir. joe

ctlotus · Answer

I have fully dis-charged and re-charged the batteries twice now and on both occasions, the system has not hibernated. Looks like this has done the trick. Would like to hear other success stories. CT.

dave843 · Answer

Well, this BIOS worked for me for a couple of days (but I didn't run it all the way down). Today the computer suspended when the media bay battery was dead but the main battery was full :-(

MDGambill · Answer

Do you think it might work if the laptop wasn't set to Hibernate or go into Standby when the power is low? Do you suppose it might switch if no action is taken? Has anyone tried this?

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D800 dual battery

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