Battery Backup For Laptop When Power Outage?

Hey all got a question. I have a dell xps 15 9550 laptop and i have it charged into outlet almost always. But if i disconnect it from outlet, i get around 2 hour battery life at the most it seem before i have to recharge it. The thing is when im doing certain things, i have to be connected for minimum 8 hours. Thus if i have a power outage and power doesn't come back, I lose money in what i do. I had this happen several times in the building where i rent from because power outages is very common.


Most of the time, the power outage isn't that long like 15 minutes. But few times its been hours and rare times its a day or so. But my main issue is when im on the computer and i can't have this happen.


I read online about ups etc. But im not sure exactly how that works. Does this mean if you have something like this and then your battery on laptop is running out of battery, you could connect your laptop to it and then charge your laptop like its an electric outlet? If so, could you basically use it like an outlet? Example say you charge it to your laptop at 10 percent battery. Say you have it charged to 100 percent and during this time, you used the laptop for another 45 minutes etc. Now you are suppose to unplug it right? Then now you get another 2 hours of it on battery? Then would there still be enough power in that device to plug it in again and charge it again? Thus it would be another 45 minutes and another 2 hours?


I read that these devices only give you like 25 minutes or a bit more than that. So basically you could never get that much power?


And can someone tell me what are examples of this on amazon?


I saw these power banks on amazon. So is this the type of device that i would need for this? Im not sure if its power bank or UPS etc.


https://www.amazon.com/MAXOAK-50000...=1538623206&sr=8-4&keywords=power+bank+laptop

https://www.amazon.com/Portable-TSA...=1538623206&sr=8-5&keywords=power+bank+laptop

https://www.amazon.com/Omars-24000m...=1538623206&sr=8-7&keywords=power+bank+laptop


I know that the bigger the mAh, the more it last. But how many hours would it last? Example say you have 2 hours of battery on laptop when power outage happens. Now you have one of these on hand. How many hours could you get additionally with one of these devices? Thus when you plug it to laptop and use it while its plugged in... then unplug it when battery is 100 percent... then use laptop while on battery for another 2 hours... is there still enough power to charge it again or is that already way too much?

 

UPSs are designed to temporarily maintain power supply in the event of power failure sufficient to enable an orderly shutdown. A UPS with a big battery may meet your needs.

You don't say which (nominal 56 or 84 Whr) battery you have in your XPS15 9550. You can check this, and your power drain when running on battery, using BatteryInfoView. If that battery can keep your computer running for two hours and you want to run for 8 hours then you need extra capacity of at least 3 times the internal battery capacity. Make that at least 4 times to allow for power conversion losses. The only one of the external batteries you identified which comes near to that target is the first one which claims 185 Whr capacity (note that Watt-hours is a more meaningful indicator of capacity than mAh as batteries can have the same mAh rating but different voltages giving different power capacities). However, there's a note on that power bank about not supplying more than 90W so it might cut out if overloaded or the computer may throttle itself if it can't identify the rating of the power source.

If your backup power supply is at a fixed location then a big automotive battery + charger + inverter could be the best solution. A 12V 60Ah battery could theoretically delivery up to 720 Whr (but assume less) and you can get a 250W 12V to mains voltage inverter quite cheaply. Just keep the battery on charge and if the mains goes off for a significant period then connect the inverter to the battery, unplug your XPS PSU from the mains outlet and plug it into the inverter. There should be enough spare power to run a light or two.

John

 

I have 56 whr battery for the xps 15 9550.


So which power bank would i need for my laptop then? This one would be what i want then right?

https://www.amazon.com/Dell-Power-C...id=1538684056&sr=8-4&keywords=dell+power+bank

 

Can you explain more?

 

@Drew1 more like couple of these https://www.amazon.com/MAXOAK-50000...=1538623206&sr=8-4&keywords=power+bank+laptop

 

The charger needs a 110 V AC power supply to function. The inverter turns the DC voltage provided by the battery into the AC power supply required by the charger.

 

The 18000mAh is meaningless by itself. The info here is that the capacity is about 65Whr so after allowing conversion losses, it's similar capacity to your internal battery. The convenience of Dell's Power Companion is that it is compatible with the computer and can be charged by the computer's PSU. The disadvantage is that you need several to run all day.

The battery + inverter is explained here. Just add a charger to keep the battery topped up (best to have an intelligent charger which has a trickle charge mode). There's nothing automatic about this setup (unlike a UPS which switches automatically) but that's no problem as the notebook has a battery which acts as a UPS.

John

 

Depending on your budget and preferences a combination of several technologies may be best suited for you. You could look into small generators. Most of these require fuel. Depending on how long it takes your battery to charge/UPS to charge you could just run it until charged then turn it off.

Something like this -
https://www.amazon.com/gp/product/B00NHACROW/ref=s9_acsd_hps_ft_cr_x__a_w

or even smaller using small propane bottles instead of gasoline
https://www.homedepot.com/p/Ryobi-900-Watt-Propane-Powered-Inverter-Generator-RYi911LP/302703564

Richard

 

Hi there. So you are telling me that getting this would mean i only get between 1 to 1.5 hours of battery only similar to my dell xps 15 9550 battery?

 

It all depends on how fast your XPS guzzles power. Can you, for example, throttle back the performance when the mains power fails? Draining a 65Whr battery an hour implies a power consumption of around 60W. I prepared this graph for my Precision 5510 (essentially the same as your 9550) when I first received it in 2016.

Limiting the CPU speed improves its power efficiency and the graph highlights the power saving which can be made by disabling turbo mode. This can be easily achieved by setting the maximum CPU state to 99% in the power plan advanced settings. Further reduction of maximum CPU state slows the CPU further although there's no simple and logical relationship. I can get 10 hours from my Precision 5510 with big battery under light usage with a moderately dim screen.

However, if you want to have your computer doing a heavy workload all day on a battery then you will need a big battery. I would suggest something such as a 120 Amp-hr 12V automotive battery with an inverter. In theory this could provide 1440Whr but allowing for power conversion losses and avoiding draining the battery too far (not good for a lead-acid battery - the inverter may automatically cut out) the usable power may only be half (a guess). Given that you don't need portability it may be a viable solution. Get one 60AH battery and see how long it will last. If not enough then add another.... You will also need a mains to 12V charger.

John

 

Hi there i have no idea what you mean by throttle back the performance. Well if there is power outage, i usually make my laptop screen dimmed pretty low and make the power to better performance instead of best performance.


Wait so if i do that setting you suggest, then i should get much more than the 1 hour to 1 hour 15 minutes with it? Well the thing is it would not be light usage. So how do i make it like that? How do i know what is my current setting for it? I mean yea i would like to do it like that to test it out and also do it while doing my thing and see how many hours i get out of it. But surely more than the current i have?


Well i only need it if there is a power outage. If no power outage, i use it plugged in along with my 2 monitors fine. But if power outage happens, well im only using my laptop. But the 18000 mAh power bank, that should get 1 hour at least right? Is it even possible to get more than that? I spoke to someone on another forum who said he has either that or similar one and mentioned he could get multiple charges with it. I dont even know how that is possible since he say he uses that all day and it last all day but did say he uses it lightly and on his bed. But still all day with it is possible?

 

If I understood your posts correctly, you live in an apartment so simplest solution of power generator is out of the questions, since they need to be outside since they run lawn mower type of engine. You probably need 200Whr to run your laptop for 8 hours so 1 car or 2 motorcycle batteries should be sufficient. You would need charger for the battery, 12vDC to 120v AC inverter and battery itself (strongly suggest AGM type, so no acid to spill). All together this could cost $100-$200. But if I was you I would buy 2 of those https://www.amazon.com/Batterymarke...y&qid=1553991679&s=gateway&sr=8-2-spons&psc=1
for $116 and just replace them as needed. I would probably take out all but 1-2 screws in place to make battery change easier. Or get older laptop with extra batteries, where battery is removed by pressing 2 tabs. What a freaking revolutionary design that was.
Another solution would be to repurpose power tool batteries, but that would require some electrical knowledge and doing your own wires, but for example Lowes has 48Whr Kobalt batteries for $20.

 

You also have to decide if you need internet access or other devices. You may need power back up

 

Internet access should be easy with USB tethering to cell phone, which in turn will also charge that phone. Printing can be done into XPS files. Few years ago I didn't have electricity after the huricane for almost a week and gas generator saved me a lot of headaches and it's best option by far, too bad it's not an option for OP.

 

Like to update this. I got the power bank for this laptop. However, it seems like i could only get 1 full charge on it and thats it. So basically with this, i get around 1.5 to 2 hours max. Reason being say my power goes out... i use the laptop on battery for 1 hour. Then say it charges for 1 hour 15 minutes. Then im on battery for the rest for another 45 minute. So that means with it, i only get 2 hours extra on it right at the very max?


I tried plugging the power bank into it when it was at 33% and let it charge to 100%. It took 1.5 hours and i still had 2 out of 5 bars left on charger. The issue though was when it was charging, i was not using my laptop much at all. So wouldnt that mean if i did, well i might not even 100% charge?


Well about UPS? If i get one of these and only use it to connect to my laptop, how long would it last? I know they are meant for desktop and for in case you could save all your files etc. But can you use it like a powerbank? If so, does it make your laptop last longer than compared to powerbank?

 

You could try this: https://www.anker.com/deals/powerhouse2
or: https://www.anker.com/products/variant/powerhouse-200/A1702111

They are a little pricey but they should do the trick.

 

So if i use that for my laptop, how long would i get out of it about? My dell xps laptop internal battery is 56wh. Example power outage. I use it on my laptop battery for 1 hour. Now i need to connect. How long could i get out of it? I estimate when i connect my fully charged power bank to it and while using it... and while using it while power charger runs out... i probably get 1.5 to 2 hours out of it max.