Wifi on all the time...a large battery drain?

[Hollow Man]

I remember when I got my Kindle Keyboard forever ago that Amazon had suggested keeping the wifi off, when possible, to increase battery life. Now many years later, with my new Oasis, I'm curious to know if this is still recommended. I don't mind it off most of the time, but if I do want to sync my place, or connect to the bookstore, it does take just long enough to turn the wifi on that it annoys me.

Thoughts?

-HM

[Shinytop]

I do not turn off my wifi on any of my devices. The Oasis will still last weeks to a month depending on how much you read. A bigger factor is the brightness of the screen. My age and developing cataracts require a setting of 18 for me and I still have no problem with battery life.

[Cinisajoy]

Only if you are out and about and it is searching for a signal.

[barryem]

The Wifi stays on on all four of my Kindles and always has. I charge them every Saturday. Usually they're down about 15% to 20% in a week. The one I'm currently reading with gets charged more often of course.

Barry

[Atunah]

Starting with the Voyage and now the Oasis, I have left wifi on at all times now. I look up stuff all the time, wiki, and I just want it to be always connected.

I go 3-4 days with my Oasis and then I have to charge it. But then I can read a book a day. Or such. I also use the goodreads recommendations on it, browse my wishlists, look around in the store.
My light is usually at 10. Just depends how much one reads really. It won't last weeks no matter what if you read a lot.

I prefer to have it on now all the time. At home of course.

[Hollow Man]

Has anyone done any measurements to see just what the average battery life goes down to by having the wifi on? Clearly the more you use it the more it drains, but I'm just curious on average if it's 25% worse as opposed to having wifi off? 50%? 75%?

-HM

I leave WiFi ON all the time on my Voyage. I rarely even open the the darn thing to read on it and it mostly sits on a shelf collecting dust. It might be three or more weeks before I open it up and see if it is still charged, and it always still has enough of a charge to turn ON. I charge it about once a month. If your Kindle is left at home mostly, then no need to worry about WiFi drain on the battery. If you are taking it out away from your WiFi, then it can be an issue as it will search for networks to join.

[Hollow Man]

My Kindle, most of the time, is in only in one of two places: my home or my work. So I don't know how much of a drain it will be in transit between those two places. I have the 3G one, so with luck it would just sit on that until it gets to its destination.

-HM

[barryem]

Originally Posted by Hollow Man

Has anyone done any measurements to see just what the average battery life goes down to by having the wifi on? Clearly the more you use it the more it drains, but I'm just curious on average if it's 25% worse as opposed to having wifi off? 50%? 75%?

-HM

I didn't actually measure anything but for a while I left the Wifi off on the Kindles i wasn't using to see if that made a noticable difference. It didn't. Charging once a week still had the things down 15% to 20% weekly. I went back to leaving Wifi on.

If there was a difference it wasn't easily noticeable.

Barry

[dordale]

Originally Posted by Hollow Man

My Kindle, most of the time, is in only in one of two places: my home or my work. So I don't know how much of a drain it will be in transit between those two places. I have the 3G one, so with luck it would just sit on that until it gets to its destination.

-HM

Why not try an experiment--leave wi-fi on for one week, note where the battery level is, charge and then leave wi-fi off for a week. Then compare battery the battery level. Assuming your usage and travel patterns are similar between the two weeks, that should give you a good idea of the battery drain caused by wi-fi.

If you do this, I'd be interested in the results. I'd think about trying something like this myself, but I always leave wi-fi off on my Voyage--mostly to avoid unwanted firmware updates.

[Hollow Man]

Originally Posted by dordale

Why not try an experiment--leave wi-fi on for one week, note where the battery level is, charge and then leave wi-fi off for a week. Then compare battery the battery level. Assuming your usage and travel patterns are similar between the two weeks, that should give you a good idea of the battery drain caused by wi-fi.

If you do this, I'd be interested in the results. I'd think about trying something like this myself, but I always leave wi-fi off on my Voyage--mostly to avoid unwanted firmware updates.

The issue with the Oasis is that the battery life gets muddled because of the cover. I've got two batteries to monitor! Every time you put the Oasis back in the cover, it charges the Oasis to about 92-93%, then stops (and drains the cover battery accordingly).

-HM

[Yourcat]

The Kindle firmware should keep WiFi off most time to save battery. At home this works fine, if there's no WiFi available it may drain the battery ... so you should disable it or use a Kindle with mobile data. But also mobile data may drain the battery if the network/signal quality is poor.
I keep WiFi off as I don't need to sync often.

[Andy_D]

This is a question about battery drain but not specifically about WiFi battery drain, however WiFi battery drain is the largest element of the issue I am raising below. I hope that's okay.

I've read that batteries in these devices have a lifespan of only ~300 charge/discharge cycles.This is probably adequate for most of you, but I like to keep things, even personal electronics, a much longer than average time, so I am wondering about the following:

I use my Kindle and Fire at home about 80% of the time. If I run them on their batteries there all the time, I estimate that the premature cause of death of the devices will be battery death. I'm not into cracking cases to replace batteries in sealed units. The batteries will also gradually lose their ability to hold a charge before becoming totally useless, so when I do take them with me when I travel, they would need more frequent recharging.

However what is the effect on the battery if the devices are left on their chargers all the time when at home, even when fully charged? It is only slightly less convenient having them attached to a USB cable.

Are there any negative effects from doing this? Does the juice to power a fully charged and plugged-in device come first from the charger (sparing the battery) or does it drain the battery first which then promptly is topped-off by the charger? My hypothesis for doing this is that the battery is effectively not being drained when the device is plugged into a power supply. However that's a guess based only on a hunch.

[barryem]

First, typical life for today's batteries is usually estimated at between 500 and 1,000 full charges, or twice that many half charges or 4 times that many quarter charges, etc. I don't know where you got your figure of 300 charges.

Like all batteries, lithium ion batteries self discharge, meaning they discharge when you aren't using them. Other battery chemistries do that more than lithium ion but they all do it. Leaving it plugged in means it's going to discharge a little and then recharge, which is likely to use up your 500 to 1,000 cycles more quickly. Tests from batteryuniversity.com show that this doesn't make a lot of difference but it does make some difference.

The best way to prolong your battery life is to keep it between about 40% and 90%. Don't go above or below that and it'll last a little longer. Again, the difference will be small.

I've been buying Kindles since 2009 and all of them since my very first are still being used regularly by people I see all the time and I'm the one they come to for help with them so I see their Kindles all the time and talk about them. I live in a retirement home with a lot of neighbors who also have Kindles and I'm the one who helps them. That's been going on since the very first Kindle in 2007. I have a couple of neighbors with those. With one exception all of them still get reasonably good battery life. That exception is an original Kindle which was left in a drawer and the battery went bad from self discharging too low. That was the only model with a user replaceable battery so it was replaced and is still working just fine.

Just guessing I'd estimate that I know 20 or more people with Kindles, most of which are several years old. Several of them, like me, have multiple Kindles. All have reasonably good batteries.

My suggestion is to just enjoy your Kindle. Worrying about it makes it less fun and probably won't make it last a lot longer. You can be fairly sure that it'll last long enough that when it does die you'll be ready for a new one.

I currently have 4 Kindles and 3 Kobos and a Nook. I charge the one I'm reading every few days, usually 2 or 3 times a week. The rest I charge every Saturday. They're usually down about 15%. I do charge them till they're full just because it's easier on me and not very hard on the Kindle. They last and last and last.

Barry

[Andy_D]

Originally Posted by barryem

typical life for today's batteries is usually estimated at between 500 and 1,000 full charges, or twice that many half charges or 4 times that many quarter charges, etc. I don't know where you got your figure of 300 charges.

Barry, Thanks for that thorough answer. I really appreciate the effort.

I got the ~300 (which probably should have been 300-500) charges from an online tech channel I used to watch: Leo Laporte's tech.tv. This question frequently came up, and that was his stock answer.

I always wondered how one should count a charge to a battery that was only slightly discharged. I worried that charging a battery that was still 80% charged would count as one full charge against that total number of charges the battery would accept. Your explanation makes good sense and is good news. I now understand that charging a 70% already charged battery counts as only about one third of one of those 300 or 1000 or however many charges that the battery will accept. That piece of information is very valuable to my battery charging concerns. I won't be leaving my devices plugged-in anymore.

Thanks again.