Charging all day bad for battery?

[96Firebird]

I recently got a wireless charging back for my Galaxy S5, and my first charging pad should be arriving today. I plan on putting the pad on my nightstand for wireless charging all night, but also want to get one for my desk at work so I can just set my phone on it and it will charge during the day as well. Is there any downside to having the battery charging for this long?

 

[pete6032]

No. Not with modern devices and batteries.

 

[Jinny]

I have a phone with built in wireless charging. The phone gets quite warm when charging it this way, whether or not this will damage phone remains to be seen.

 

[JAG87]

No. Not with modern devices and batteries.

Wow. Yes it will.

A lithium battery will suffer from staying at high voltages for extended periods. Keeping the battery at 100% for extended periods after charging has ceased is BAD.

OP, try to keep your battery between 25-75% if you want to keep your battery healthy. With wireless charging this should be pretty easy to do. Don't leave your phone on it overnight.

 

[rcpratt]

Don't leave your phone on it overnight.

How is this different than normal charging? I'm not going to start waking up at 2AM to unplug my phone when it finishes.

 

[dguy6789]

Wow. Yes it will.

A lithium battery will suffer from staying at high voltages for extended periods. Keeping the battery at 100% for extended periods after charging has ceased is BAD.

OP, try to keep your battery between 25-75% if you want to keep your battery healthy. With wireless charging this should be pretty easy to do. Don't leave your phone on it overnight.

Wow, no it won't. Stop perpetuating myths that don't relate to modern battery technology.

There is no tangible drawback from leaving your phone on charge the entire time you aren't using it. The phone's battery capacity will still be within the range that would be considered normal for the age of the battery years later even if it was on charge for its entire life.

 

[rcpratt]

dp

 

[ChronoReverse]

Wow. Yes it will.

A lithium battery will suffer from staying at high voltages for extended periods. Keeping the battery at 100% for extended periods after charging has ceased is BAD.

He mentioned modern devices because they have hardware specifically preventing that.

Your phone will charge to "100%" (in quotes because it's also smart enough to not actually come close to overcharging your battery) and then the charging circuits disconnect themselves. The software is then smart enough to report 100% despite the battery slowly discharging to about 90% (which can take days when your device is plugged in). This way, the recharge cycles are minimized while maintaining a charge level higher than 70% which would inhibit usefulness.



The only exception to leaving it plugged in is if you plan to long-term store the battery without using it. In that case, you do want to leave it at 70% charge and in a cool (but not frozen) location.

 

[pete6032]

Wow. Yes it will.

A lithium battery will suffer from staying at high voltages for extended periods. Keeping the battery at 100% for extended periods after charging has ceased is BAD.

OP, try to keep your battery between 25-75% if you want to keep your battery healthy. With wireless charging this should be pretty easy to do. Don't leave your phone on it overnight.

No. This is a myth. Modern devices will stop charging when they hit 100%.

 

[JAG87]

LOL, just goes to show how little people know about battery technology and why people constantly have shit battery life after not even 2 years.

First of all, it doesn't matter that chargers stop charging at 100%.

A battery will be practically dead after a year (under 80% retained amperage) if it's maintained constantly at 100% voltage, while it will be over at almost full retained amperage if it's maintained at 50% voltage over the same length of time.

Depth of charge/discharge also affect it's life. It's better to do 10x 50% charge/discharge cycles, than 5x 100% charge discharge cycles. This also permits the battery to charge at lower temperature, as the duration of a 50% charge cycle is less than a 100% cycle. Charging all the way to 100% and keeping it there is about the worst thing you can do to a lithium battery, and it's why so many people have a shot battery after less than 500 cycles.

These are facts from the field, not myths. If you can't wake up at 2AM to unplug your phone, then keep going the way you're doing it. Nobody is asking you to turn your life upside down. But with the OP having a wireless charger at home and at work, there's no reason he can't put a little bit of attention and actually end up with a useable battery after 2 years instead of one that barely makes it though the day.

Any questions?

 

[Belegost]

I've had a Lumia 920 that I have been wirelessly charging all night and frequently dropping it on the pad at the office for the past two years, I have yet to notice any significant reduction in battery life.

 

[ChronoReverse]

LOL, just goes to show how little people know about battery technology and why people constantly have shit battery life after not even 2 years.

First of all, it doesn't matter that chargers stop charging at 100%.

A battery will be practically dead after a year (under 80% retained amperage) if it's maintained constantly at 100% voltage, while it will be over at almost full retained amperage if it's maintained at 50% voltage over the same length of time.

Any questions?

Yes, if you don't even know what the correct technical terms are, how much of your "layman's" knowledge is actually useful?


Even the part about partial cycles wasn't terribly useful since while it's technically correct, modern phones and chargers don't actually put your battery to 100% charge in the first place!

It's also ridiculously naive since people actually USE their phones and need the full battery life. Furthermore cutting 50% of your battery life in a vain attempt to keep the battery life over 70% of its original capacity doesn't make any sense! You're complaining about the battery's capacity dropping to 80% of the original when you're advocating using only 50% of it in the first place!

Depth of charge/discharge also affect it's life. It's better to do 10x 50% charge/discharge cycles, than 5x 100% charge discharge cycles. This also permits the battery to charge at lower temperature, as the duration of a 50% charge cycle is less than a 100% cycle. Charging all the way to 100% and keeping it there is about the worst thing you can do to a lithium battery, and it's why so many people have a shot battery after less than 500 cycles.

 

[ChronoReverse]

With all that said, wireless charging does in fact generate a lot more heat than regular charging (especially compared QuickCharge 2.0 capable devices that don't get as hot) which is very bad for the battery. You're basically trading off convenience here.

When your phone is fully charged, the heat won't be generated anymore but while it's charging, you are indeed actively increasing the rate the battery capacity drops. My phone is a Galaxy S4 so it's not a hard choice to go for the convenience when I can swap the battery easily but if you have a non-removable battery and plan to use it for longer than 3 years, it's worth considering (although my opinion is that in three years you'd likely be getting a new phone anyway).

 

[JAG87]

Yes, if you don't even know what the correct technical terms are, how much of your "layman's" knowledge is actually useful?


Even the part about partial cycles wasn't terribly useful since while it's technically correct, modern phones and chargers don't actually put your battery to 100% charge in the first place!

It's also ridiculously naive since people actually USE their phones and need the full battery life. Furthermore cutting 50% of your battery life in a vain attempt to keep the battery life over 70% of its original capacity doesn't make any sense! You're complaining about the battery's capacity dropping to 80% of the original when you're advocating using only 50% of it in the first place!

This isn't meant as a guide to revolving your life around your battery.

If you have the chance to top off (like someone who HAS A CHARGER AT WORK?), then you have no excuse for doing 100% day drain cycles and 100% nightly charge cycles. You're just lazy and you'll either 1. replace your battery after 18 months because your 100% day drain cycle isn't feasible anymore, or 2. trade/sell your phone with a dead battery after 2 years to an unfortunate unaware buyer who now has to factor in another expense after buying a used phone.

Plus, if you have a phone that lasts longer than a day, like most phablets, using your battery at only 50-60% depth is not unreasonable at all.

Is that clear enough?

 

[rcpratt]

It's certainly pretentious enough.

 

[JAG87]

It's certainly pretentious enough.

Well, by the same logic proper diets and exercise are also pretentious routines... most people live to be 80 anyways by medicating one way or another, so doesn't matter how you get to 80...

Interpret it as you like. The OP asked a question, and this is the correct answer.

 

[Zaap]

Eh. Just another reason I love removable batteries. Don't care either way, a brand new battery is dirt cheap and a mere swap away.

 

[rcpratt]

Well, by the same logic proper diets and exercise are also pretentious routines... most people live to be 80 anyways by medicating one way or another, so doesn't matter how you get to 80...

Interpret it as you like. The OP asked a question, and this is the correct answer.

Oh, not the advice. How you're delivering it.

 

[Lat]

OP, try to keep your battery between 25-75% if you want to keep your battery healthy. With wireless charging this should be pretty easy to do. Don't leave your phone on it overnight.

A battery will be practically dead after a year (under 80% retained amperage) if it's maintained constantly at 100% voltage, while it will be over at almost full retained amperage if it's maintained at 50% voltage over the same length of time.

Just to reiterate what you're saying - you're suggesting only ever charging the phone up to 75% because you're scared it will only retain 80% of its off-the-shelf capacity? That sounds like flawed logic.

ChronoReverse is correct - modern charging circuitry doesn't actually constantly top off the moment the battery drops from 100% to 99%; it will discharge to 90%, trickle charge back up, so on so forth.

OP, as you suggested is perfectly fine for the battery, pragmatically

 

[poofyhairguy]

You know, I can't wait for this tech to filter down to non-cell phones. I wish my weedeater, or cordless vacuum cleaner charger would be smart too and stop at 100%.

 

[Capt Caveman]

LOL, just goes to show how little people know about battery technology and why people constantly have shit battery life after not even 2 years.

First of all, it doesn't matter that chargers stop charging at 100%.

A battery will be practically dead after a year (under 80% retained amperage) if it's maintained constantly at 100% voltage, while it will be over at almost full retained amperage if it's maintained at 50% voltage over the same length of time.

Depth of charge/discharge also affect it's life. It's better to do 10x 50% charge/discharge cycles, than 5x 100% charge discharge cycles. This also permits the battery to charge at lower temperature, as the duration of a 50% charge cycle is less than a 100% cycle. Charging all the way to 100% and keeping it there is about the worst thing you can do to a lithium battery, and it's why so many people have a shot battery after less than 500 cycles.

These are facts from the field, not myths. If you can't wake up at 2AM to unplug your phone, then keep going the way you're doing it. Nobody is asking you to turn your life upside down. But with the OP having a wireless charger at home and at work, there's no reason he can't put a little bit of attention and actually end up with a useable battery after 2 years instead of one that barely makes it though the day.

Any questions?

My Nexus 10 would prove you wrong. I keep it charged all day for years but can take it with me for a weekend and it'll still have more than 50% with a lot of usage.

 

[GTRagnarok]

I don't know what JAG87 is going on about. All the devices I've used aren't even warm at all when plugged in and full. Sounds a lot better than charging like normal and heating the battery. My 5.5 year old laptop has been plugged in at least 80% of that time, almost every night, and it's at 35% wear, which sounds pretty good to me. My 14 month old MacBook Pro has been plugged in about 95% of its life (every night) and it's at 3% wear.

 

[bandi]

No. Modern handsets stop charging once they hit 100%. That's why sometimes you'll find your phone at 97% or 98% because it stopped charging and discharged a little bit before it started recharging back up to 100% again

 

[mmntech]

Modern Lithium-ion charging circuitry shuts off when the battery reaches its peak voltage. So there's no risk in overcharging the battery. Once it's full, the device will run off mains power.

 

[eelw]

Just monitor the heat. If it gets too warm during the day, take if off the charging pad.