Replacing the Batteries in Your Logitech K800 Wireless Keyboard

Do you have a Logitech K800 Wireless Keyboard? Does the keyboard no longer hold a charge? Does the charge LED just flash red? In this article I’m going to show you how to fix it.

My K800 is at least four years old and the batteries will no longer hold a charge. Logitech never meant for the batteries in these keyboards to be user replaceable and doesn’t offer a replacement service.

The good news is that you can replace the batteries yourself. The K800 uses two NH-Mi rechargeable AA batteries. To change them.

  1. turn the keyboard power switch off
  2. turn the keyboard upside down
  3. use a small phillips head screwdriver to remove the screw holding the batter cover in place
  4. slide off the battery cover. It may be a little tight but it comes off
  5. remove the AA battery on the left. It comes out pretty easy
  6. remove the AA battery on the right. It has a tighter fit and their is some black plastic covering it
  7. replace the batteries. I used Duracell batteries. The one on the right is a little harder to insert but it will go in
  8. replace the battery cover on the keyboard. You may need to flex it a little to get it back in place
  9. put the screw back in
  10. turn the keyboard on and check to make sure that the K800 turns on
  11. you are done

Here is a link to the Duracell Rechargeable batteries on Amazon.

Amazon Links
Duracell Rechargeable AA Batteries-
Energizer Rechargeable AA Batteries –
Logitech K800 Wireless Keyboard –

I did want to say a few words about the Logitech K800. I own three of these keyboards and they are great. These keyboards are wireless and as you can see in the video the K800 is backlit so you can see the keys in the dark. Since the K800 is wireless, it uses a small USB wireless receiver, called the unifying receiver, that will let you pair multiple Logitech wireless devices with your Mac or PC. The keyboard uses Logitech’s propriety wireless technology, not Bluetooth, so you need to use the receiver.

I use my keyboards with both my PC and Mac. The keyboards work with both. I currently don’t even have the Logitech software installed on my computers. I am not sure if there is Mac software for them though as I initially set them up using Windows.

As I said in the video, some of my keyboards are over four years old and Logitech still makes this model so it must be a popular product.

44 thoughts on “Replacing the Batteries in Your Logitech K800 Wireless Keyboard”

  1. Right, never meant for them to be user replaceable. Which is why they’re standard AA batteries under an obvious battery cover held on by the most common of screws.

    1. My guess is regular AA batteries would work until they died out. But if you plugged in the USB cable and tried to recharge them you could have unpredictable results including the chance of fire or damaging the keyboard as regular batteries are not made for recharging.

      Also, the keyboard isn’t really designed for easily changing the batteries.

    1. One further question, if you don’t mind. I have just received this keyboard and I like it a lot, but the 3 second delay before the illumination shuts down makes using the KB difficult for me. I see that it will stay on when the charger is plugged in, but I don’t plan on leaving it plugged in constantly. Is there a way to make it stay on longer than 3 seconds? Thanks! John

  2. Actually, I do have one more. I have a Logitech receiver from a previous Logitech KB (K330) along with the matching wireless mouse, but the mouse won’t work without the new receiver. The old one also has the orange asterisk and looks identical, but the K800 won’t work with the existing receiver. So, I have to have both plugged in all the time. Is there something I can do to make the existing mouse and the new KB both work with a single receiver? Thanks again

  3. I solved the device recognition problem by downloading the software and telling it to recognize the old mouse. Only the timeout problem remains…

  4. I have the “Dell by Logitech” wireless keyboard KM714 and mouse WM514 that use a unifying receiver. It says Dell on it but I’m assuming it’s made by Logitech just like the keyboard and mouse. I’m looking to replace this keyboard with the K800. Can I use the existing receiver?

    The wireless is neat for as much as it’s really needed with a desktop computer. I’m planning on just keeping it hooked up and charged with a short USB cable plugged into one of the USB ports on my monitor. This way I feel like I have the best of two worlds, without having to mess with swapping out batteries or turning the keyboard on and off – backlit, and wireless if I ever really need it.

    1. Hi Martin,
      I don’t know for sure. Best I can tell by looking at Dell, Logitech and a couple google searches, I’d think it would. Check the return policy for the K800 before you buy. You can also use 2 unifying receivers on one PC. I do that sometimes when I am swapping around keyboards and mice. Never had an issue. Heck years ago, you’d need a separate transceiver for a keyboard and mouse if they weren’t from a combo.

      If I were buying new, I’d also consider the K830. It supports Bluetooth as well. You’d have to decide if you like the keys and touchpad.

      I can’t say it would cause an issue, but you might want consider occasionally unplugging the USB cable and let the batteries cycle.

      1. Thanks tech128! Bluetooth is nice, but my desktop doesn’t have that built in to begin with. I just happened to get my wife the MX Anywhere 2 mouse though, also for it’s bluetooth option as an USB dongle looks bad with her Surface Pro 4. Also like the K800 design better as it corresponds with that of my Dell monitor with it’s silver edge as does my current KM714. I’ll post here how it went, should I get the K800.

        1. Sound good. I am a big MX Anywhere 2 fan. I use it with Bluetooth with my Macbook Pro and a Unifying Receiver on my desktop PC. I wish the would update the K800 and add that same connectivity. Turns out the K830 is on sale at Best Buy this week. Thinking of getting on for my living room PC.

  5. That is a good deal. I was getting tempted until I read that the K830 has no caps lock indicator. Or am I missing something? That’s been the only other thing besides no illumination bothering me about my KM714. So I guess it’s going to be the oldschool-ish K800. Man I wish I had two desktop PC to cover, I’d get both 🙂

  6. Does anyone have a suggestion? Key board was a gift about 2 years ago

    I followed the about instructions but when the new batteries [Duracell Rechargeable] were put in I got a message “batteries unknown”. It would not work plugged in and did not indicate it was charging. It would work plugged in with the old batteries but would not charge. I tried a different cable before changing the batteries and the USB ports are all fine on my computer.

    Do the batteries need to be charged before they are put in? Could that make them unrecognizable? It is a new pack I bought yesterday.

    Thanks in advance for any help. I miss the back light so would really like to ‘fix’ this.

    1. Hi Kris,
      This is the first time I have heard this issue. The batteries in my pack were fully charged when I bought them. Did you test yours in a flashlight or other product? My sugestion:
      1. check that the batteries are charged. If not return them. They should come charged.
      2. If you bought a four pack, try the other two in the keyboard.
      3. Try them again making sure you inserted them in the correct orientation. (I know, you probabally did)

      I have a few of these keyboards, I think I also used Energize rechargables too.

      1. I would say I am 99.99% sure I put them in correctly but I will admit I am not 100% certain.

        I charged them and now they seem to work fine. Perhaps they had been on the shelf too long at the store. I am typing on the key board now and it seems to be working just fine.

        According to my external charger when I put them in they read flat so that might have been the trouble — again it could have been me though normally I would have checked some thing like that.

        Thank you for the swift answer.

  7. I replaced my batteries with 2 brand new Ni-MH rechargeable batteries that match the engraving on the inside of the keyboard exactly. AA 1.2V Ni-MH
    The keyboard holds a charge for about 2 minutes
    Do the batteries need to be replaced with Duracell brand rechargeable?

    1. Mike,
      I have used Duracell and Energizer but I don’t think those brands are required. I had one reader that bought new batteries that required a full charge before he could use them. He never said afterward if the keyboard was able to charge them. If it were me, I’d try a different set of batteries.

      1. Thanks for your reply tech, I recall that post
        I’m not sure what I did differently, but removing replacing the replacement batteries seems to be all it took
        Maybe they just weren’t making contact properly
        Either way, I’m glad we all were able to revive our keyboards!!
        7 years strong with this bad boy!!

  8. I think the K800 is a winner. I just bought two of them two weeks ago and I cannot imagine using anything else anymore.

    And to think I previously splurged on mechanical keyboards of all kinds trying to find the ‘right’ keyboard for me when the single K800 that cost half of a mechanical keyboard ended up being the most comfortable solution.

    1. Nice point. The K800 used to sell for about $100, but you can find for much less now. I have three, and recently gave one to a friend, who was amazed by the backlighting. I wish they would update the K800, add Bluetooth support in addition to the universal wireless receiver.

  9. Thank you! I was concerned about having to replace this keyboard when it started dying. Yes, it is a winner and I’m glad I don’t need to replace it. Your fix was perfect. Using it now.

    Thanks again

    1. While AA batteries will work, I don’t recommend it. You don’t ever want to plug in the USB cable and have the keyboard charge regular AA batteries. Also I much rather just pay for rechargeable batteries that last for years.

  10. Watched video for replacing k 800 batteries, but it appears the batteries you used are not 2000 mAh, but are higher amperage. Does this matter?

    1. Hey, I’ve never had a problem. I don’t think its an issue. Other readers and viewers use different ones. No one has reported a problem. I think its more important to stick with NiMH batteries as that is what the keyboard was designed to charge. A couple people told me they put Alkaline batteries in, I’d think that is dangerous if you plug the USB cord in.

  11. Just want to clarify some things about the batteries. I saw some questions about brands and which capacities.

    Virtually any AA battery should make the keyboard work. But people are right that you may have bad situation if you plug in the USB charging cable while non-rechargeable batteries are installed. Brand doesn’t matter.

    There is nothing special about the AA batteries used in this keyboard. They’re just regular Ni-MH rechargeable cells, which are a standard AA size and a nominal 1.2 volts. In fact I use the very same Eneloop branded rechargeable batteries in my torches, bathroom scales, portable radio, cordless mouse, etc.

    Basically the keyboard has a Ni-MH battery charger built-in and therefore if you are going to plug in the USB charging cable then you have to have installed Ni-MH rechargeable cells. That’s it.

    You can use regular AA ‘heavy duty’ or alkaline (both NON-rechargeable) batteries in the keyboard and I’m sure it will work – but if you then plug in the charging cable it’s the same as inserting non-rechargeable AA cells into a desktop battery charger. Both the batteries and the charger warn you not to do it. I’m not sure what would happen but the warnings on the cells usually say something like ‘Do not recharge, may leak or explode if recharged’. So that’s that. Don’t do it.

    If you’re in a pinch, maybe your batteries are flat and you can’t find your microUSB charging cable and you NEED to use the keyboard – just go ahead and pop in any AA batteries and use the keyboard without worry. Just DON’T plug in the charging cable while they’re in there. Be aware that alkaline cells can be prone to leaking if left sitting so long term it is best to stick with the Ni-MH for our nice keyboards.

    Now, about Ni-MH battery types. Brand doesn’t matter. Duracell, Energizer, Eneloops by Panasonic (or previously Sanyo) – they will all be a nominal 1.2 volts which is the main thing. Any capacity value will work (like 1800mAh or 2600mAh). It’s just a smaller capacity means you’ll have to recharge the batteries more often (plug in the cable). So probably best not to use the cheap 800mAh ones designed for cordless phones or solar garden lights.

    However – be aware there IS a difference between the original type of Ni-MH cells that you’ve been able to buy for decades, and the newer Low Self-Discharge (LSD) type of Ni-MH cells. The Eneloops that came in my K800 are the LSD type. What that means is that they take much much longer to go flat on their own (self-discharge). The curse of rechargeable batteries used to be that if you put them in a torch or camera or radio, they’d often have gone flat or nearly-flat again on their own by the time you picked up that item up to use it a few weeks later. That has changed with LSD batteries. LSD Ni-MH batteries will hold a good amount of charge for many many months if not years. That means if this keyboard is seldom used, like at a spare desk or rarely used media PC, then you’re best off buying LSD type Ni-MH batteries as replacements. I suspect that’s why Logitech shipped these with Eneloops. Eneloops are highly respected Ni-MH cells btw. I’m actually surprised to read some of you are having to replace them – I’ve got some nearly 10 years old that I’m still using but I guess it depends how much use they got over the years.

    One trade-off with LSD cells is the slightly different construction means they don’t have as high a maximum capacity as non-LSD Ni-MH cells. So that’s why although Eneloop batteries are highly respected, they are ‘only’ rated for 1900mAh whereas you can buy other Ni-MH batteries that might be rated 2600mAh for example. I’d be wary of cheap brands claiming capacity figures much higher than that.

    SO – if you are using your keyboard every day and depleting the batteries within a month or so, it doesn’t really matter if you get the LSD type or not since you’ll be recharging them regularly anyway. But if like mine your K800 sits long periods without use, then best stick to an LSD type of Ni-MH cell. Sometimes they’re not specifically labelled as low self-discharge but the packaging often states ‘pre-charged’ or similar. Because they don’t go completely flat while they’re on the shop shelf.

    Regular grey/blue Eneloops, originally made by Sanyo but now sold to Panasonic, are probably the best well known ones.

  12. CAUTION!

    I just bought a K800 because I liked the keyboard when trying it in the shop and because I have seen so many tutorials how to replace the old batteries if required – so I can still use the keyboard in a couple of years when the day comes, that the internal batteries will not work any longer.

    And now the sad news: the current version of the K800 does NO LONGER have AA batteries inside! Even though there is still a cover with a screw, you will just see white plastic under it – no battery compartment any longer! It seems logitech decided to replace the batteries with an internal version which can NOT be replaced at all.

    So Logitech clearly wants to sell more keyboards and does not want the users to replace parts. Shame on Logitech! 🙁

    1. Yes. This is true. And people should be aware of it. Thanks for the comment It’s been noted in the video comments too.

      A few points. 1. According to the manual, the batteries in the older K800’s were not user replaceable. The screw and that black plastic holding the batteries in are a clear indication that these batteries were not meant to be changed by consumers. 2. I always thought the use of AA batteries was problematic, as I bet some people replaced the NiHM batteries in this keyboard with alkaline ones which is dangerous. 3. This isn’t new for logitech. For years they have made rechargeable products, that required removing hidden screws and then trying to source some non standard battery.
      4. It may still be possible to replace the batteries with far more effort. It may require prying open the keyboard (I don’t think its screwed together)

      I don’t like it, but it 2019 its a common practice for consumer electronics.
      I realized the other day that I have a pair of Bose QC35 headphones and I don’t know if the battery can be replaced when it dies. sigh.

  13. Thanks for all the info tech128 and contributors.

    My KB is about 5 years old and lately, my batteries would last about 3-4 days using it 2-3 hours a day. I have a USB cable near by so it wasn’t a big deal.

    I left for a 3 week vacation and when I came back, the KB batteries were Dead. I tried to charge them but I would only get a flashing red light and they wouldn’t charge.

    I thought I could try the battery that came with the accompanying mouse (Logitech Performance MX) but that didn’t work. Then I tried charging the KB batteries in the Mouse and that worked.

    So now, I am able to charge the KB batteries with the KB.

    Before you dispose of the batteries and get new ones, you might want to try and charge them with a different charger.

    Thanks again everyone !

    1. Hey Dave,
      Glad the info helped. and thanks fore sharing the charging tip. I’ve heard a few similar reports of using an AA charger too.

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