Fast charging and battery life

t3chg33k

Skilled
But isnt 10W very less ? These days 25W is standard with expensive devices going on to 65W chargers also
Yeah, but I have an iPhone which maxes out at 7.5W and really going to use it at night time by the bedside.

The higher wattage chargers are simply going to kill the battery. At the end of the day, physics and chemistry dictates that the battery will be heated to a much higher temperature with higher voltage, thereby accelerating its degradation. Also, the efficiency of wireless charging is quite poor as it requires a 18W charger to effectively provide 7.5W.

If your life doesn't require you to charge the battery to 80% in 30 minutes, then it is better to go with a lower wattage charger. Only use fast charging if you really need it. Too bad that most manufacturers have taken out the option of slow charging.
 
Yeah, but I have an iPhone which maxes out at 7.5W and really going to use it at night time by the bedside.

The higher wattage chargers are simply going to kill the battery. At the end of the day, physics and chemistry dictates that the battery will be heated to a much higher temperature with higher voltage, thereby accelerating its degradation. Also, the efficiency of wireless charging is quite poor as it requires a 18W charger to effectively provide 7.5W.

If your life doesn't require you to charge the battery to 80% in 30 minutes, then it is better to go with a lower wattage charger. Only use fast charging if you really need it. Too bad that most manufacturers have taken out the option of slow charging.
Many new phones have dual battery, and the higher charging simply denotes 2 batteries filling out simultaneously (I think OP8T, and a bunch of Realme, Mi and chinese stuff). Ingenious, I would say.
 
Many new phones have dual battery, and the higher charging simply denotes 2 batteries filling out simultaneously (I think OP8T, and a bunch of Realme, Mi and chinese stuff). Ingenious, I would say.
I had a 7T previously with the Warp Charge 30T charger as well as a voltmeter/ammeter which measured the voltage and current draw by the phone. I don't remember the exact numbers now but it stays at 9V/2+A till the halfway mark, then drops to 5V and high amperage till about 80-90%, before dropping to a low amperage at 5V.

If the phone is drawing that much voltage and current, then it means the battery is also getting charged at that level since most of the charging circuitry is in the charger. In case of dual batteries, the current draw is mostly being split between the two batteries to allow them to charge simultaneously but since the batteries are now smaller, it is actually killing the batteries faster.

Of course, the headline is about how fast the battery charges and not how quickly it will die because they want you to change the phone as soon as possible with most not bothering to replace the batteries at several thousand bucks.
 
I had a 7T previously with the Warp Charge 30T charger as well as a voltmeter/ammeter which measured the voltage and current draw by the phone. I don't remember the exact numbers now but it stays at 9V/2+A till the halfway mark, then drops to 5V and high amperage till about 80-90%, before dropping to a low amperage at 5V.

If the phone is drawing that much voltage and current, then it means the battery is also getting charged at that level since most of the charging circuitry is in the charger. In case of dual batteries, the current draw is mostly being split between the two batteries to allow them to charge simultaneously but since the batteries are now smaller, it is actually killing the batteries faster.

Of course, the headline is about how fast the battery charges and not how quickly it will die because they want you to change the phone as soon as possible with most not bothering to replace the batteries at several thousand bucks.
You have the option to use a slow charger of 3 or 5w if you want. It is an option
Though you might need to buy an iPhone charger as I don't think anyone else makes those slow chargers in this age


Your claims of faster charging causing device harming high temperatures are just baseless and hypothetical. There are several videos on youtube comparing charging time and temperatures of iphone 12 vs other flagship and sub 30k or sub 20k phones. No significant difference in temperature. 3 degrees or so if i remember right
 
There is plenty of material that indicates faster charging can kill batteries faster. It's pretty simple physics based on the expansion rate of lithium dendrites. If you search for it, it's out there.

Since i use my phone for PC data, usb tethering means my phone charges at a slow and steady 500mA. I haven't used a regular charger in ages.
 
On the issue of charging , to be truthful i dont care . The mobiles dont last that long with me as i upgrade in less than 2 years . Time and fully charged mobile is more important than the battery which costs around 500/800 for most Androids including Samsung flagships after 2 years
 
It's not the cost of the battery, it's the trouble to change it. When we had user-removable batteries it was no biggie. My current phone, the asus 5z actually needs the back panel heated to loosen the glue holding it in place. And then the glue sticker is supposed to be replaced not reused. Yeah, i'm sure the Indian service centers will do that...

Also the time thing is immaterial. On a slow, low power charge overnight, there will be far less battery damage than a quick charge. I don't see why people can't use a low power charger overnight and get the battery ready to go at 100% in the morning.
 
There is plenty of material that indicates faster charging can kill batteries faster. It's pretty simple physics based on the expansion rate of lithium dendrites. If you search for it, it's out there.

Since i use my phone for PC data, usb tethering means my phone charges at a slow and steady 500mA. I haven't used a regular charger in ages.
to counter the heat issue, oneplus divided it's battery into 2 and then both are charged simultaneously.
 
Any lipo battery inside is good for 1c charge rate, anything higher causes it bulge very soon. i.e 4.2v x (AH capacity of the battery) in Amps = watts.
So a G8x for eg 4.2v x 4ah=16.8watt is the max you can charge for long life.
 
course, the headline is about how fast the battery charges and not how quickly it will die because they want you to change the phone as soon as possible with most not bothering to replace the batteries at several thousand bucks.
Several thousand bucks ? I don't know about others, but I got my Pixel 2 XL's battery changed via BCD aka official service centre. 1100 for the battery, 500 for labor. Pretty cheap.
I checked for P4a (which I'm toting now), and it's battery is even cheaper - 863 bucks. So if I've to get it changed OFFICIALLY, it's just 863+500.
No idea about other brands.
 
Any lipo battery inside is good for 1c charge rate, anything higher causes it bulge very soon. i.e 4.2v x (AH capacity of the battery) in Amps = watts.
So a G8x for eg 4.2v x 4ah=16.8watt is the max you can charge for long life.
So basically for most phones these days around 18W charging won't cause major issues.
BTW, I used a phone with 18W fast charging for 2 and a half years and it lost only 2hrs SoT - from 7 to 5. The same phone is still being used by Mom and it gives around 4-4.5hrs SoT.
 
You have the option to use a slow charger of 3 or 5w if you want. It is an option
Though you might need to buy an iPhone charger as I don't think anyone else makes those slow chargers in this age


Your claims of faster charging causing device harming high temperatures are just baseless and hypothetical. There are several videos on youtube comparing charging time and temperatures of iphone 12 vs other flagship and sub 30k or sub 20k phones. No significant difference in temperature. 3 degrees or so if i remember right
I suggest you read stuff from proper sources rather than watch YouTubers with half baked knowledge, as otherwise you will find every fact to be baseless and hypothetical.

Every degree impacts the battery, not to say a lot of the cheaper phones use cheap sensors for the battery that don't even provide the correct reading.

To quote:
Apply the ultra-fast charge only when necessary. A well-designed ultra-fast charger should have charge-time selection to give the user the option to choose the least stressful charge for the time allotted. Figure 2 compares the cycle life of a typical lithium-ion battery when charged and discharged at 1C, 2C and 3C rates. The longevity can further be prolonged by charging and discharging below 1C; 0.8C is the recommended rate.


Cycle performance of Li-ion with 1C, 2C and 3C charge and discharge
Figure 2: Cycle performance of Li-ion with 1C, 2C and 3C charge and discharge.
Charging and discharging Li-ion above 1C reduces service life. Use a slower charge and discharge if possible. This rule applies to most batteries.
 
I suggest you read stuff from proper sources rather than watch YouTubers with half baked knowledge, as otherwise you will find every fact to be baseless and hypothetical.

Every degree impacts the battery, not to say a lot of the cheaper phones use cheap sensors for the battery that don't even provide the correct reading.

To quote:
Only sources you read and want to believe being an apple fan and a boy... Are reliable... Everyone else in the world is foolish and unreliable and crap

Got it. Great bias. Keep going


Ofcourse evry degree impacts the battery that is just so obvious. Its like saying water is wet.

The key question is what is the best temperature for minimum wear for the battery. I'm sure you will believe when apple tells you 2w is best. When they say 15w is best you will find research to support that.
They also said who needs a stylus and a big screen and now they are saying who needs faster refresh rate or a charger or a headphone jack. Don't blindly support whatever phone you have or company you want to believe in. Question them. Challenge them.
 
Only sources you read and want to believe being an apple fan and a boy... Are reliable... Everyone else in the world is foolish and unreliable and crap

Got it. Great bias. Keep going


Ofcourse evry degree impacts the battery that is just so obvious. Its like saying water is wet.

The key question is what is the best temperature for minimum wear for the battery. I'm sure you will believe when apple tells you 2w is best. When they say 15w is best you will find research to support that.
They also said who needs a stylus and a big screen and now they are saying who needs faster refresh rate or a charger or a headphone jack. Don't blindly support whatever phone you have or company you want to believe in. Question them. Challenge them.
It is unfortunate that you have to push your bias on everyone else. Out of the past 10 years, I have used iPhone for only 3. I primarily use my Samsung Galaxy Tab at home. It seems you are blinded by some hate for Apple, because I give a damn about any company when I am paying to own their device.

What I will give them is that their business and marketing decisions are well planned with a proper roadmap and execution which is what makes them the biggest hardware company in the world with 3 times the profit of Samsung.

To continue on the original discussion, I have disabled fast charging on my Samsung tablet since Day 1 which limits charging to 80% capacity at the usual 5V/2A level. I charge it overnight and it lasts me through the day. Now that is a more practical implementation without relying solely on gimmicks.
 
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To continue on the original discussion, I have disabled fast charging on my Samsung tablet since Day 1 which limits charging to 80% capacity at the usual 5V/2A level. I charge it overnight and it lasts me through the day. Now that is a more practical implementation without relying solely on gimmicks.

One of my friends still uses a 5V 1A charger and he would call your methods as fast charging and detrimental to battery life. Yes, if one can afford to, then they should definitely charge at slowest speeds possible, but battery tech has improved a lot and charging at 1C isn't bad at all for battery life.
Companies might not be providing slow chargers inside the box but they are easily available in market or most people will already have them. So it's better that the companies provide fast charging tech and adaptors for people who need them.

I am a very heavy user in terms of SoT. On my older phone, battery used to run out for me at mid-day, so I could appreciate the fact that the phone came with 18W fast charging so I could charge it up quickly. When I bought a new phone, it had insane battery life and it would last me the whole day with just 50% battery used so I used to charge it only till 80% every night with a 10W charger, like you do, even when it came with a 33W charger, which I never even took out of the box. I could have even used a 5W charger or charged through the USB port of my laptop at 2.5W if I wanted to.

So, the point I am trying to make is that it is better to have fast charging tech and chargers for the time one might need them as one can always charge on slower speeds as per their convenience. It is a very common saying that, 'It is better to have it and not need it than need it and not have it'.
 
One of my friends still uses a 5V 1A charger and he would call your methods as fast charging and detrimental to battery life. Yes, if one can afford to, then they should definitely charge at slowest speeds possible, but battery tech has improved a lot and charging at 1C isn't bad at all for battery life.
Companies might not be providing slow chargers inside the box but they are easily available in market or most people will already have them. So it's better that the companies provide fast charging tech and adaptors for people who need them.

I am a very heavy user in terms of SoT. On my older phone, battery used to run out for me at mid-day, so I could appreciate the fact that the phone came with 18W fast charging so I could charge it up quickly. When I bought a new phone, it had insane battery life and it would last me the whole day with just 50% battery used so I used to charge it only till 80% every night with a 10W charger, like you do, even when it came with a 33W charger, which I never even took out of the box. I could have even used a 5W charger or charged through the USB port of my laptop at 2.5W if I wanted to.

So, the point I am trying to make is that it is better to have fast charging tech and chargers for the time one might need them as one can always charge on slower speeds as per their convenience. It is a very common saying that, 'It is better to have it and not need it than need it and not have it'.
It is okay to have fast charging if the manufacturers don't break normal charging. Last year I was on a trip and was draining my 7T when using the camera. I had a 18W power bank with me and it was absurd that 7T charged at less than 5W without its own charger or cable. The phone was draining faster than charging when using the camera.

All the non-BBK brand phones without the proprietary Warp, SuperVOOC technology were able to charge at 18W with the power bank. These fast charging technologies hinder other chargers and also their own chargers work ridiculously slowly with other devices.

At least Qualcomm Quick Charge is compatible with USB-C PD. While it fast charges any phone using their power management IC, they still work at the normal USB PD specification on other phones. Hence, I think the proprietary fast charging technologies being touted by the Chinese manufacturers are generally harmful in more ways than one.
 
It is okay to have fast charging if the manufacturers don't break normal charging. Last year I was on a trip and was draining my 7T when using the camera. I had a 18W power bank with me and it was absurd that 7T charged at less than 5W without its own charger or cable. The phone was draining faster than charging when using the camera.

All the non-BBK brand phones without the proprietary Warp, SuperVOOC technology were able to charge at 18W with the power bank. These fast charging technologies hinder other chargers and also their own chargers work ridiculously slowly with other devices.

At least Qualcomm Quick Charge is compatible with USB-C PD. While it fast charges any phone using their power management IC, they still work at the normal USB PD specification on other phones. Hence, I think the proprietary fast charging technologies being touted by the Chinese manufacturers are generally harmful in more ways than one.
Dude now you have gone on a completely different tangent altogether (which I don't have a problem with).
Every company has the right to develop proprietary tech. Yes it might not be everyone's cup of tea but every company would like to be independent in fields as essential as charging for their product.
FYI, even QC protocol is a Qualcomm proprietary technology.
Yes, a standard charging protocol would be great, especially when companies are now starting to remove chargers from the box, but cooperation among tech companies is not something which happens very easily.
 
One of my friends still uses a 5V 1A charger and he would call your methods as fast charging and detrimental to battery life. Yes, if one can afford to, then they should definitely charge at slowest speeds possible, but battery tech has improved a lot and charging at 1C isn't bad at all for battery life.
Companies might not be providing slow chargers inside the box but they are easily available in market or most people will already have them. So it's better that the companies provide fast charging tech and adaptors for people who need them.

I am a very heavy user in terms of SoT. On my older phone, battery used to run out for me at mid-day, so I could appreciate the fact that the phone came with 18W fast charging so I could charge it up quickly. When I bought a new phone, it had insane battery life and it would last me the whole day with just 50% battery used so I used to charge it only till 80% every night with a 10W charger, like you do, even when it came with a 33W charger, which I never even took out of the box. I could have even used a 5W charger or charged through the USB port of my laptop at 2.5W if I wanted to.

So, the point I am trying to make is that it is better to have fast charging tech and chargers for the time one might need them as one can always charge on slower speeds as per their convenience. It is a very common saying that, 'It is better to have it and not need it than need it and not have it'.
Hey i was using a 750mA charger till it died about 6 months ago, and instead of switching to my 1A and 2A chargers (got a handful), I decided to just stick to USB's 500mA now. I can understand the need for fast charging sometimes, but if you understand basic Li-ion chemistry and how V/A affects it, you wouldn't fast charge if you can help it.
 
After using battery at highest fast charging ability if it dies after 18 months getting it replaced is so much cheaper in android phones that I would say it is totally worth it.
For example replacing pixel 4a battery via authorized way costs something like 1.3 - 1.4k. That turns out to less than 100 rupees a month.

Easily worth it for me. Again option to the customer to choose a fast or slow charger

Apple on the other hand charges 6000 to replace a battery and that too is slow as hell. What's the use of charging slowly if you anyways end up paying much higher to apple.

Again no option to the customer. Cost save for apple to use old tech. Charge higher for replacing old tech. All power and money to apple.
 
There is plenty of material that indicates faster charging can kill batteries faster. It's pretty simple physics based on the expansion rate of lithium dendrites. If you search for it, it's out there.

Since i use my phone for PC data, usb tethering means my phone charges at a slow and steady 500mA. I haven't used a regular charger in ages.
Yes and that is why I am against fast charging. Infact I don't use my default fast charger that was bundled with Redmi Note 9 Pro max. I use an old one which is also fast but not like the Pro max one (I got no standard charger or else I would have used that one)
 
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