The Galaxy S22’s 45 W charging doesn’t actually improve charge times
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Shocking. It's almost like there are physical/chemical/electrical/thermal constraints that you run into.
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So... the phone just outputs more heat when charged with 45 watts? This smells like a creative marketing department.
*Edit* Based on the comments, I may have jumped the gun here. Apologies to the marketing department. You do smell great ... today.
*Edit* Based on the comments, I may have jumped the gun here. Apologies to the marketing department. You do smell great ... today.
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This again.
Just because someone doesn't understand how batteries are charged, doesn't mean it's misleading. Does Samsung say a 45W charger will charge the phone from dead to full faster than a 25W charger, but it doesn't? That would be a problem. If that's not the case, and instead the phone can only pull 45W within a certain range of SoC and/or for a certain time window, that's to be expected. Unfortunately, the linked graphs from GSMArena are useless. They didn't provide a charging curve. Instead we get an extremely useless bar graph of simply "charge time."
Just because someone doesn't understand how batteries are charged, doesn't mean it's misleading. Does Samsung say a 45W charger will charge the phone from dead to full faster than a 25W charger, but it doesn't? That would be a problem. If that's not the case, and instead the phone can only pull 45W within a certain range of SoC and/or for a certain time window, that's to be expected. Unfortunately, the linked graphs from GSMArena are useless. They didn't provide a charging curve. Instead we get an extremely useless bar graph of simply "charge time."
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I'm years off from my electronics theory courses, but unless I'm missing something, across the board it looks like the gains from pumping more watts into wireless charging are reduced no matter how high you get with current (pun!) technology. If a 25W charges half as fast as a 65W or 80W solution, then it seems like the amount of loss increases the more power is put in. It certainly isn't a clean scale since a 50W charger would be twice as fast as a 25W, and an 80W three times, but if even an 80W is only twice as fast, then until battery and charging tech improves it might be better to stick with the higher efficiencies of lower watt solutions.
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Total charging time to 100% isn't the main appeal of ultra-fast charging, even if manufacturers try to mislead the public into making it seem like it does. I see fast charging to be most useful in situations where you have 10-20 minutes during your day to charge your phone, and fast charging at full power can very well top 50% of the battery during that time, giving you enough juice to last the rest of the day into the evening. Fast charging is for short bursts of charging during the day, rather than measuring how long it does take to go from 0 to 100%.
This can negate the need to carry around a bulky and heavy powerbank that often needs to be tethered to the phone for a much longer amount of time, saving you weight and hassle.
This can negate the need to carry around a bulky and heavy powerbank that often needs to be tethered to the phone for a much longer amount of time, saving you weight and hassle.
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They're not talking about wireless charging in the case. Unless I missed something.
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I'm no Samsung fan (first and last Samsung phone was the Galaxy Nexus), but no one has demonstrated that the phone can't pull 45W. Maybe they can't and Samsung is trying to pull a fast one on us, but someone should actually demonstrate that then instead of draining a phone to dead, charging it to full, and just saying "look, it wasn't fast! It can't be pulling 45W!"
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I mean, I'm not offended in the slightest. Just think the race to up the charging wattage is slightly asinine and very much a "bigger numbers sell" specsmanship.
And yes, I do like having fast charging in general. But it's already at a pretty good state. And the more they try to stuff in, the more likely you are to get battery degradation over time.
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I don't know why I'm going to bat for a major corporation, but the firmware for an unreleased product may not fully optimize 45W charging yet. Early adopters are used to features not fully working at launch.
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No, I likely did. My bad, I assumed it was. Honestly though, that makes this look even worse. At least with wireless, you could blame a lot of the loss on just radiated energy loss, but if wired charging still has the loss, that loss has to go somewhere, and my guess is heat. Wireless, you can blame the loss on just radiated energy that wasn't captured by the phone. This loss with a wired solution just looks like wasted engineering and for the sake of marketing.
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Does the S22 still require USB-C PD PPS in order to fast charge at 25W or 45W?
I have a few USB-C PD chargers that are 65W, but the charging speeds with the Galaxy S21 Ultra are limited because the charger isn't PPS. It isn't as big an issue if you upgrade to newer chargers, but it makes the already confusing world of USB-C charging even worse because there is one more acronym to check before you buy.
I have a few USB-C PD chargers that are 65W, but the charging speeds with the Galaxy S21 Ultra are limited because the charger isn't PPS. It isn't as big an issue if you upgrade to newer chargers, but it makes the already confusing world of USB-C charging even worse because there is one more acronym to check before you buy.
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Did they put a power meter on it or did they just look at the charging time? Having watched most of my devices charge, they ramp up the power input slowly while monitoring the thermals then ramp down again as the batter gets full. The ramp-up/down can take longer than the actual charging. So the peak wattage might be 45W while the time-averaged value is nearly indistinguishable from the 25W run. That's potentially very true is the battery wasn't well-drained and in the sweet-spot for fast charging.
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Sammobile's review is more useful as it does show the benefit of the 45 w charger (i.e., at the start).
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If that is the case, then why bother even updating it for 45W? Seems like a waste of effort for a useless number.
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It's not loss. A charger doesn't "put out" a fixed amount of current. A phone draws what it draws. You could use a new, facing USB PD charger capable of supplying 200W, but if your phone only wants to draw 20W for charging, the charger is only going to see a 20W load. That doesn't mean you have 180W of heat.
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Because marketing!
But seriously, for some devices when really empty, a fast charge can put 20% in very quickly. But then thermals and voltage potential require that to scale back. But being able to charge 10% in just a few minutes is really quite game changing.
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Because it's very likely it's pulling 45W for a period of time, and that period could be beneficial. If you only ever charge your phone from dead to full overnight, then you don't need fast charging at all. If you're in a situation where you can only charge for 5-10 minutes, being able to pump in twice as much charge over that short period, that makes a difference.
It's the same thing we see with EVs. Those "350kW" cars are not pulling 350kW for more than a few minutes and only if the battery is at proper temp and state of charge. If you're too empty or too full, too hot or too cold, you can't push that much energy into the battery without causing it harm. But when the conditionsnare right, can you can cram a massive amount of energy into the battery in a short period of time. It may not add up to much if you need to do a full 0-100% charge because you're going to spend so much time charging slowly from ~80% to 100% or whatever, and you might have to spend some time slow charging at the beginning to warm up the battery, but if you just needed to get 20% to make sure you make it home, you'll be happy to see some of that being done at a much higher rate than the overall average would have been.
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Then Xiaomi and Oneplus are breaking the laws of physics !... Or Samsung is lying.
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I propose we start differentiating our terminology:
Battery Longevity: How long the battery maintains 90% of it's advertised Wh. Its Full Useful Life.
Battery Life: How long the battery can power the device during expected usage.
Anywho...
45w may only be reached in certain environmental conditions. Like, the battery is between 20 and 80%; it is 30°C ± 5°C; etc. I'm willing to give them the benefit of the doubt.
Battery Longevity: How long the battery maintains 90% of it's advertised Wh. Its Full Useful Life.
Battery Life: How long the battery can power the device during expected usage.
Anywho...
45w may only be reached in certain environmental conditions. Like, the battery is between 20 and 80%; it is 30°C ± 5°C; etc. I'm willing to give them the benefit of the doubt.
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hardly surprising.
my note 10 + advertised that it can pull 45w, but i believe that only applies if you phone charge from 0 to 5%, anything after that drop to sub 20w range. meaning 45w or 25w charger makes about 5 minute difference if you charge from 0 to 100 percent, and you often don't find any difference at all.
my note 10 + advertised that it can pull 45w, but i believe that only applies if you phone charge from 0 to 5%, anything after that drop to sub 20w range. meaning 45w or 25w charger makes about 5 minute difference if you charge from 0 to 100 percent, and you often don't find any difference at all.
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Or perhaps they don't give a lick about battery longevity.
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So, if the thing actually charges in the same amount of time yet manages to pull an extra 20W, where is that power going if it's not in the battery?? is it just burning that power as heat?
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Total charge time is a useless metric because batteries don't charge at the same rate throughout charging. Temperature permitting, fast charging's impact only really matters in around the first half of the charge. As others pointed out, they failed to provide a graph of how much power was being delivered to the phone over time.
I suppose it's also a problem with manufacturers who say "Fast Charging!" but it only practically applies to a certain range in the battery's charge state.
I suppose it's also a problem with manufacturers who say "Fast Charging!" but it only practically applies to a certain range in the battery's charge state.
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except you won't get anywhere near 45W unless you phone is at 0 percent. that's how Samsung has traditional implemented fast charging, and i am pretty sure applies here too.
in your use case, the phone never likely exceed 25w charging.
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Is there any rationale left in charging slowly - provided you have the time, perhaps on old usb port on your PC? I have had numerous accu/battery powered devices and slow charging always seemed to work for better capacity retention.
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I'll take the slower charging and the fact the battery will actually last the full 2-3 years I keep a phone vs. the super fast charging killing a battery much faster.
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Yes, this is pretty lightweight analysis when it would be dead simple to just strap it to a Kill-A-Watt and graph the actual wattage over time from dead to full.
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I understand capability of a charger vs. what a phone can take in, but the understanding here is that a phone taking 25W is charging only half as fast as a 65W or 80W phone is, even when those phones are supposedly pulling that much from the wall (reading the last paragraph of the article for citation). If there was no loss, wouldn't it scale appropriately? In other words, a 25W phone charging a 1 unit per hour scaled to 50W to charge 2 units in an hour, which would scale to 75W for 3 units in an hour, but instead, we're seeing a 25W phone charge at only half the rate of a phone that is pulling in over three times as much.
Of course, this is also assuming that the citated area of the article takes into consideration the phone's capacity, and that the phones in question are pulling their rated power as well (which, if not.... I mean, why even bother adding it to the article?)
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the 30min test says it all
you don't even need extra hardware to confirm this, phonetinfo will tell you the charging/discharging current and voltage in real time
you don't even need extra hardware to confirm this, phonetinfo will tell you the charging/discharging current and voltage in real time
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Whether by accident or by Ron's general antipathy toward Android, this misses the point that the 45W charging is more about accelerating the bottom of the charging curve than the whole.
Basically, you will get to 60-80% faster, but then slow down dramatically and pamper the battery up to 100%.
Basically, you will get to 60-80% faster, but then slow down dramatically and pamper the battery up to 100%.
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Fast-charging a near-dead battery to barely resuscitated isn't going to kill it any faster.
The OnePlus charging that really is double speed, that's where longevity is concerning. Though swapping the battery (or entire phone) more often in exchange for much faster charging is an acceptable tradeoff for some.
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You have to admit that despite the truth of that, Samsung's marketing is in no way going to highlight that fact.
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Even then the benefit is minimal. You get about 6% extra battery with a 20 minute charge on the 45W charger vs. the 25W charger. An extra 10 minutes reduces the benefit of the 45W charger even more (1-2% more battery power after 30 minutes vs. the 25W).
Aside from their marketing, Samsung is mostly guilty of hopping aboard the charging spec train and trying to chase the Chinese brands. Per the GSM Arena article, "Much like it has been for the past two years, you'd need an hour to get a full charge."
A whole hour! The horror!
Stick with the 25W charging and save a few bucks.
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I think you are on to something. Not sure this is the case for phone chargers, but at the last percentages of charging, a charger switches from injecting a large current into the battery to "constant voltage" mode. It just applies a DC voltage and lets the last charges trickle in. This can take quite a while. Look at the charger of i.e. a cordless drill. Up to 80% goes really fast, then it slows down a lot. So if that time dominates the charging time, no wonder it is not much faster.
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I get why having a phone that charges to full in 60-90 minutes not 3 hours is useful - at least when you forget to charge it overnight, but beyond that who cares? When are any of us really away from a plug for all that long except when camping or something?
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