Why the 45W fast charger not supported?

[BlackZeppelin]

Hi all. I have a Galaxy Note 9 and very seriously considered getting the S21 Ultra. I have instead decided to wait for the S22 series at which I'll definitely upgrade.

I'm really curious why the S21 series does not support the 45W fast charger that has been available for a few years now. I have a theory;

A brand new unreleased Samsung 65W fast charger has been seen online. I'm speculating that Samsung is preparing to release this in their next flagship, either the Note 21 (if it's released at all), or the S22 series.

A lot of videos have been posted comparing the 25W and 45W fast chargers from Samsung. And they are unanimous. The 45W fast chargers aren't a lot faster than the 25W ones. If the 65W charger is released, inevitably there will be a heap of comparisons between that and the 45W charger. And I can't imagine that it'll be hugely faster than the 45W charger. It's the same 20W difference between the 25W and 45W charger.

But...........

Take out the 45W charger and introduce a 65W charger and the comparisons will be hugely favourable. There should be a big difference between 25W and 65W fast charging without the middling 45W charger.

Samsung has to compete with Chinese OEM's, unlike Apple that is a market to itself. Brands such as Oppo, Huawei, Xiaomi etc are running streaks ahead of Samsung in charging capabilities, both wired and wireless. At some point Samsung has to catch up in this area. As an aside, I think Samsung did a brilliant job in surpassing the optical zoom capabilities of the Huawei P40 Mate Pro in such a short space of time. To go from 4x optical to 10x optical in a year with less refracting than Huawei is outstanding.

Thoughts about my theory on the fast charging?

 

[fuzzylumpkin]

Honestly I just think Samsung are weird and/or cheap.

They've always been a few years behind on charging tech. not to mention doubling the charging power the same year you don't provide a charger for the first time seems like a recipe for bad press.

 

[Mooncatt]

Without getting too deep into the weeds, charging Li-ion batteries can be a delicate science, and that is the limiting factor.

In general, Li-ion batteries can be charged at a rate equal to their capacity without stressing the battery too much. For a 5000 mAh (5Ah) like what is in the S21 Ultra, that equates to a maximum 5A of input current. The voltage going into the battery (not the output voltage of the charging brick) maxes out at 5V for safety reason.

Wattage is voltage time amperage. 5V x 5A = 25W.

To charge at 45W, the calculation works out to 5V @ 9A. It takes extra care in the charging algorithms to do that, plus the battery needs to be specially designed to handle the increased charging current without wearing out too soon. Doing so necessarily makes the battery larger, meaning a more bulky phone that people don't want.

As you already mentioned, the 45W charger wasn't much faster anyway, and neither would a 65W charger. Charging happens in stages. The first stage when the battery is low is where higher current is applied. As the battery is filled, charging current must be cut back or it'll damage/destroy the battery. The faster you charge during the first stage, the longer the second stage takes. With the 45W charger, you'll see quicker charging and time savings to 60-70%, but you loose most of that advantage above that. Assuming it's possible to charge at 65W (13A) safely, that second slower charging stage will begin even sooner.

Long story short, the biggest reason the 45W charger isn't compatible is simply due to physics and the waste of money to buy that charger. Many on this forum recommend against it for this reason.

 

[Gayle Lynn]

Does faster charge equate to more heat generated during charge, and higher temperature levels so you might be seeing 40°C?

 

[Mooncatt]

Does faster charge equate to more heat generated during charge, and higher temperature levels so you might be seeing 40°C?

It can, which I think is why the need for more bulk when charging faster than standard. The added bulk is to add more surface area to the plates inside, allowing for quicker charge absorption. In essence, it's like adding extra lanes on a highway to remove a bottleneck.

By the same token, a higher capacity standard battery design naturally allows for higher current as well. A 13,000mAh (13Ah) battery could definitely make use of a 65W charger. But again, it's added bulk that the market in general doesn't want.

 

[Dualmonitors]

Where were you able to see that the 45-watt fast charger isn't supported please? Thanks.

 

[bill-e]

If I have a phone that lasts all day I usually charge them overnight on a timed, low wattage charger. I leave the fast charging for those occasions that I need it. While I've never performed a scientific study, I believe that fast charging will reduce battery life and I've been operating in this manner for years.

 

[jlangner]

I have never felt need for anything above 25W. The extra cost to save 5 minutes was no biggie to me.

 

[Rose4uKY]

I have never felt need for anything above 25W. The extra cost to save 5 minutes was no biggie to me.

Well someone told me on here to get 25W over 45W back before the official announcement and we thought the Ultra might do 45W. And we have plenty of the old ones maybe 4 or 5 but I wanted the 25 since the phone supported it and am getting 2 from Samsung with my phone. I'll give one to my husband.

 

[fred134134]

I have never felt need for anything above 25W. The extra cost to save 5 minutes was no biggie to me.

Samsung has to be doing some throttling because the charging overall should be much faster than saving 5 to 10 minutes.

 

[jlangner]

This was on XDA before. https://forum.xda-developers.com/t/45w-charger-is-slower-than-25w-charger.4020781/

 

[Rose4uKY]

as i was in a rush to pre-order right after the Samsung Unpacked video presentation, i didn't look closely enough at the accessories for charging and thus, i ordered the incorrect 45-watt fast charger, thinking that as the S20 Ultra specifically can use the 45-watt fast charger, there's no reason for them to make it NOT compatible with the S21 Ultra and force us to downgrade to a 25-watt charger - WRONG!

apparently, only the 25-watt charger is listed as being compatible and the 45-watt, by inference, is incompatible. very odd.

looking over the chargers that i have, which all of course look similar, i read the fine print on a few of them and they are very different:

the black charger is the one that came with my S20 Ultra:

EP-TA800 (came with my S20 Ultra)
Input: 100-240V, 50-60 Hz, 0.7 A
Output: PDO: 5.0V 3.0A or 9.0 V 2.77A
PPS: 3.3-5.9V 3.0A or 3.3-11.0V 2.25A

additionally, i have two others that have identical specifications but have DIFFERENT model numbers:

EP-TA20JWE and DP-TA200
Input: 100-240V, 50-60 Hz 0.5A
Output: 9.0V 1.67A or 5.0V 2.0A

Wonder which one(s) are best suited for the S21 Ultra without causing damage and yet takes best advantage of its fast charging capabilities?

I tried looking at ours we have some black ones and white ones. Some from my S9 Plus and his Note 8 and 2 from our Dex's we got with our Note 8's. And the ones from our S10+. We have several laying around somewhere and I tried to see if a couple of mine were the same or what they said and I had to download a magnifier just to see LOL! I don't remember now though what they said. I think 2.0 output if I remember right they all day Fast Adaptive Chargers on them I believe. But now I am getting 2 x 25W from Samsung. Now I'm curious to look again.

 

[Dualmonitors]

as i was in a rush to pre-order right after the Samsung Unpacked video presentation, i didn't look closely enough at the accessories for charging and thus, i ordered the incorrect 45-watt fast charger, thinking that as the S20 Ultra specifically can use the 45-watt fast charger, there's no reason for them to make it NOT compatible with the S21 Ultra and force us to downgrade to a 25-watt charger - WRONG!

apparently, only the 25-watt charger is listed as being compatible and the 45-watt, by inference, is incompatible. very odd.

looking over the chargers that i have, which all of course look similar, i read the fine print on a few of them and they are very different:

the black charger is the one that came with my S20 Ultra:

EP-TA800 (came with my S20 Ultra)
Input: 100-240V, 50-60 Hz, 0.7 A
Output: PDO: 5.0V 3.0A or 9.0 V 2.77A
PPS: 3.3-5.9V 3.0A or 3.3-11.0V 2.25A

additionally, i have two others that have identical specifications but have DIFFERENT model numbers:

EP-TA20JWE and EP-TA200
Input: 100-240V, 50-60 Hz 0.5A
Output: 9.0V 1.67A or 5.0V 2.0A

Wonder which one(s) are best suited for the S21 Ultra without causing damage and yet takes best advantage of its fast charging capabilities?

For example, what if one would use the EP-TA200 or the EP-TA20JWE (identical specifications) on the S21 Ultra? would it still function fine and would the S21 Ultra be "happy" with it and the only issue is that charging would be slow?

Or, would the output be so low that the S21 Ultra would NOT be happy with it and it can thus cause problems?

 

[fuzzylumpkin]

as i was in a rush to pre-order right after the Samsung Unpacked video presentation, i didn't look closely enough at the accessories for charging and thus, i ordered the incorrect 45-watt fast charger, thinking that as the S20 Ultra specifically can use the 45-watt fast charger, there's no reason for them to make it NOT compatible with the S21 Ultra and force us to downgrade to a 25-watt charger - WRONG!

apparently, only the 25-watt charger is listed as being compatible and the 45-watt, by inference, is incompatible. very odd.

looking over the chargers that i have, which all of course look similar, i read the fine print on a few of them and they are very different:

the black charger is the one that came with my S20 Ultra:

EP-TA800 (came with my S20 Ultra)
Input: 100-240V, 50-60 Hz, 0.7 A
Output: PDO: 5.0V 3.0A or 9.0 V 2.77A
PPS: 3.3-5.9V 3.0A or 3.3-11.0V 2.25A

additionally, i have two others that have identical specifications but have DIFFERENT model numbers:

EP-TA20JWE and EP-TA200
Input: 100-240V, 50-60 Hz 0.5A
Output: 9.0V 1.67A or 5.0V 2.0A

Wonder which one(s) are best suited for the S21 Ultra without causing damage and yet takes best advantage of its fast charging capabilities?

For example, what if one would use the EP-TA200 or the EP-TA20JWE (identical specifications) on the S21 Ultra? would it still function fine and would the S21 Ultra be "happy" with it and the only issue is that charging would be slow?

Or, would the output be so low that the S21 Ultra would NOT be happy with it and it can thus cause problems?

Both of the chargers you listed will work fine. The first at 25W and the second at 15W

The 45W charger you bought from Samsung IS compatible with the S21, but obviously will only charge at 25W.

 

[Dualmonitors]

Both of the chargers you listed will work fine. The first at 25W and the second at 15W

The 45W charger you bought from Samsung IS compatible with the S21, but obviously will only charge at 25W.

thanks for the comment/advice.

if the 45-watt charger is compatible with the S21 Ultra and will NOT cause problems, why wouldn't they show it properly on samsung.com? i went to their mobile accessories page and selected my new phone, the S21 Ultra, and selected power accessories, and it ONLY gave the 25-watt charger as the only option!

may i ask how we may be certain that the 45-watt charger would be properly recognized by the new S21 Ultra and it will tell the charger to NOT use its full 45-watts?

 

[fuzzylumpkin]

If you want me to guess, I'd say because pushing a $50 charger that works no better on the S21 than their $20 charger is a lawsuit, or at least bad press, waiting to happen.

 

[Dualmonitors]

If you want me to guess, I'd say because pushing a $50 charger that works no better on the S21 than their $20 charger is a lawsuit, or at least bad press, waiting to happen.

true. still, they ought to tell current 45-watt charger owners that it is compatible with their soon-to-arrive S21 Ultras!!!

sheesh.

btw, @fuzzylumpkin, may i please ask how you knew that it will be still compatible with the S21 Ultras but merely charge at a slower rate? how do you know these chargers are "smart" and will recognize that it is to only produce a slower charge with the S21 Ultras? thank you in advance.

 

[fuzzylumpkin]

There are 2 ways i know it will work. First, i actually understand how fast charging and USB-PD work, all of those numbers you posted from the label on your chargers made perfect sense to me. Second, as i type this my S10e is plugged into a third party 45W charger lol.

 

[Dualmonitors]

May i please ask what usb-pd means?

Thank you.

 

[fuzzylumpkin]

USB (universal serial bus PD (Power Delivery)

How it basically works is, to take your charger as an example (look at "PDO" which is short for "Power Delivery Objects") , it will start charging at 5V which is basically safe for every phone. Then, if your phone is compatible with 9V it "tells" the charger and the charger starts outputting 9V.

I understand it might be a bit scary putting your new $1200 phone at risk because a random person on the internet told you it's ok, but it really is haha. Like I say, my main charger is a 45W one and this phone only supports 15W.