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  • PeachNCream - Monday, June 8, 2020 - link

    Better solution - move the heat generating and heat sensitive components outside the phone and into the charger and add a small fan to said charger. The buck-converter can be elsewhere and so can its heat. Additionally, moving the SoC package (heat source) to the charger can also be accomplished to cope with limited thermal environment of the phone. Put the battery outside the phone as well and then consider the heat problems of the screen and stick them in the charger. In fact, the screen could be in its own casing. Then you could also attach a keyboard and mouse to the phone via their own casings so there is no longer a need for a touch-enabled screen. Given that you have basically unlimited power from the charger and a larger heat budget, you could enlarge the charger to add more storage space, heatsinks and fans, and even modular upgrade options like a graphics processor or RAM that could be removed or added via expansion slots. You could even make the SoC modular by putting it into a socket so the end user could open the charger casing, remove the heatsink, lift something like a tiny metal lever to release the SoC and then drop a newer, faster one inside before putting it all back together!

    Sweet Fist of the North Star - someone get on that right away! We could be on the verge of an information technology revolution that brings thermally unlimited phone computing capabilities to power outlets across the entire world! Homes, businesses, even blended home-businesses! All of them could use these new devices to connect to and communicate with the rest of the world! Sending letters via the post office could be a thing of the past. Getting porn from a paper magazine will disappear into a world comprised entirely of ones and zeros sent over data connections! An entire industry of self-made journalists could rise up to type articles about the way a device looks or how fast it is compared to some competing device while ignoring moronic, verbally-abusive reader feedback for one tiny little typo that slipped past the editor.
  • brucethemoose - Monday, June 8, 2020 - link

    Also, QC2 seemed to be even *more* aggressive than later generations, hence I strongly suspect it contribited to the bricking and exploding phones of the Note 7/6P generation.
  • brucethemoose - Monday, June 8, 2020 - link

    Oops, wrong reply...
  • qap - Monday, June 8, 2020 - link

    Battery charging voltage in phones (or any device with single cell lithium battery) is around 4V. At that voltage you would need 10+ Amps to fastcharge (~25Amps for the proposed 100W charging). That would mean really thick cables that are not standard (ie special cables just for charging). So putting buck elsewhere is not a realistic possibility.

    Separate case for battery is not viable anymore either and I don't think that anyone would want a phone where you have to take the battery out to charge it. And obviously you would be loosing the one big benefit of USB-C - common charging for majority of devices.
  • DanNeely - Monday, June 8, 2020 - link

    On the plus side, a giant 10A plug would require phones large enough to have a battery several times bigger than current ones are, along with equally enlarged camera optics allowing for substantially better baseline image quality before the AI replaces what the camera actually saw with magical guesses.
  • BedfordTim - Monday, June 8, 2020 - link

    Spot on.
  • Santoval - Monday, June 8, 2020 - link

    Did you seriously not realize that Peach was jesting?
  • jospoortvliet - Wednesday, June 10, 2020 - link

    Half the internet conspiracy theories came to life when some idiot took a joke seriously. At least that is my conspiracy theory. Think of gems like flat earthers, anti-vaxxers and even trump voters in general... without the internet where any moron can say anything and make other morons feel like it is a reasonable thing to believe, none of that would have existed.

    Though homeopathie, crystal healing, acupuncture and alien abductions clash with my theory but, as do proponents of all above mentioned craziness, I will ignore this evidence and blindly believe I am right.
  • deil - Tuesday, June 9, 2020 - link

    I miss that battery replacement. In Samsung solid era I had 3 batteries for that phone and replaced them like a magazine. 1 in backpack, 1 at home charging, and one inside phone.
    full month of battery time even if used.
  • Sushisamurai - Tuesday, June 9, 2020 - link

    @qap you know that @PeachNCream just described a desktop computer right? It was a pretty good comparison. If only cellphones were that modular.
  • bcronce - Monday, June 8, 2020 - link

    USB chargers are great because you don't need to invest into $100 custom chargers for each phone. Anyway, you'll still need all of these parts in the phone for things like wireless charging.

    And battery chargers are custom complex circuitry for every battery type. I'd rather deal with slower charging than owning $1000 of chargers for everything I use. Which charger goes with which device again? Sounds like hell.
  • greenwoodin - Tuesday, June 9, 2020 - link

    The article talks about the charger IC inside the phone, not the wall charger outside the phone. The charger IC is compatible with USB chargers, so you don't need to invest in $100 custom chargers. It's saying the charger IC inside the phone is much more efficient, dissipates way less heat, so it can charge faster without getting the phone too hot.
  • s.yu - Thursday, June 11, 2020 - link

    Uh, no. It talked about how with all these new fast charging tech >18W the phone offloaded circuitry to the charger.
  • Fluffywings - Monday, June 8, 2020 - link

    @PeachNCream I loved every word of your comment.
  • 1_rick - Monday, June 8, 2020 - link

    F
  • BillyONeal - Monday, June 8, 2020 - link

    That's kind of what USB PPS (Programmable Power Supply) is supposed to do. The difficulty with taking that too far though is you start getting substantial losses in wiring (from the charger to the phone) and the connectors as the current increases. Your phone battery wants 3.3V but USB wants to run at 20V to reduce wire current.

    As far as I know the closest to the idea you posit here is what OnePlus does with their 'Warp Charge' tech but even that steps down from 5V to 3.3V in the phone. And it's frustrating to use because it only works with their charger and their cable since both are rated for the much higher than standard operating current.
  • greenwoodin - Tuesday, June 9, 2020 - link

    Exactly. What switched-caps do is work like Warp Charge, except it doubles or triples or quadruples the voltage, and reduce the current to 1/2, 1/3, 1/4 to keep the cable rated to be within standard operating current.
  • MrSpadge - Monday, June 8, 2020 - link

    About fast charging damaging the battery more quickly: I've searched for a software way on Android to limit fast charging when I'm in my home WIFI and it's bedtime. Couldn't find any other solution than using an older "slow charger" besides the bed and to take the fast one while traveling.
  • ads295 - Monday, June 8, 2020 - link

    Your phone settings should have an option to turn off fast charging.
  • brucethemoose - Monday, June 8, 2020 - link

    On the topic of battery degredation, theres some fascinating analysis of Qualcomm Quickcharge on the XDA forums. Where "normal" chargers slowly ramp up charging voltage until the battery hits 90%, QC ramps up to max voltage at like 20%, and only backs off if the battery overheats.
  • Andrei Frumusanu - Monday, June 8, 2020 - link

    That sounds like nonsense, because that's literally not possible.
  • shadowjk - Monday, June 8, 2020 - link

    The point at which it will reach full voltage depends on the battery's internal resistance and the charging rate.. so if either the battery is very shitty or the charging current is very high I suppose it could be possible.

    Without knowing their methodology, another possibility is that often times I've seen the voltage measurement points being closer to the charging circuit than to the battery. In other words the voltage measured by the power management circuitry is influenced not only by the battery's internal resistance, but also by the resistance of the circuit board itself, and potentially any current measurement shunts.
  • brucethemoose - Monday, June 8, 2020 - link

    You're right, my brain and memory were playing tricks on me. Heres the thread I was thinking of:

    https://forum.xda-developers.com/showpost.php?p=66...
  • bcronce - Monday, June 8, 2020 - link

    My wife and I both use lower end wireless chargers. They're slower, but fast enough. Keeps the batteries lasting longer. And the cradle for the wireless charger lets the phone face her, which on its own is useful. She is much more likely to not let her phone die if it is more convenient to charge it.

    Pre wireless charger: "Honey, can you put my phone on the charge, it's down to 30%"
    Post wireless charger: Phone rarely gets lower than 50% and she no longer asks me to "out it on the charge".
  • extide - Monday, June 8, 2020 - link

    The standard way to charge a LiION battery is a constant current mode at somewhere around 1C (or less if the charger isn't capable of that, and a bit greater than 1C in cases of some really fast charging systems) until ~75-80% capacity, then it will switch to a constant voltage charge to top it off -- which would be somewhere between 4.2 and 4.4v depending on the exact battery.

    Naturally, charging in constant current mode is going to vary the voltage in order to keep the current the same, and that means the voltage will rise over time as the cells state of charge rises.

    Some systems are more aggressive than other but they all work this way.
  • torndar - Monday, June 8, 2020 - link

    <quote> 2-3C (Coulomb).</quote>

    The "C" number is not "coulomb" it's "capacity". A 1C rate means charging the battery at a rate that would fill it in exactly 1 hour. 2-3C rate means charging it at a rate that would fill it in 30-20 minutes.
  • drexnx - Monday, June 8, 2020 - link

    that's only true if the capacity is measured at a 1 hr discharge rate, most lithium cells (at least 18650s) are measured at C being a 2 or 3 hour discharge.
  • drexnx - Monday, June 8, 2020 - link

    (but otherwise the math is correct)
  • mkozakewich - Wednesday, June 10, 2020 - link

    Thank you! I kept seeing references to C, and I was like, "Aren't amps in coulombs per second? Measuring rate in coulombs would make no sense."
  • Drake H. - Monday, June 8, 2020 - link

    Meh. I wouldn't trade a battery that lasts several years for fast charging. What we really need is a new battery technology, which results in higher power density and fast charging translating into several days of autonomy. :P
  • dwbogardus - Monday, June 8, 2020 - link

    I think my phone, a Motorola V-120, which I purchased in 2001, must have the best charging system of any I've ever heard of, from a battery lifetime standpoint. It is the only cellphone I've ever had, and I use it daily. It is using the original Motorola Li-ion battery, which until a couple of years ago acted as if it were brand new. Now it is starting to show signs of age, with only about an hour of continuous talk time, though days of standby time. It spends all night every night plugged into its pre-USB charger, and obviously doesn't mind being plugged-in continually. It has to have the best charging/battery management system I've ever heard of: 19 years, and still going! I'm glad Trac-fone is still supporting it, although I'm afraid they're going to drop support at the end of this year, and my phone may not make it to the twenty-year mark. I love reliable equipment.
  • Drake H. - Tuesday, June 9, 2020 - link

    I think it charged fast without damaging the battery because the old phones had small batteries.
  • ads295 - Monday, June 8, 2020 - link

    What we actually need is a less dumb market that puts less value on thinner phones, understands CPU performance for what it really is, puts high value on AMOLED displays, and is fine with slow charging.
    Put together a 5.5" AMOLED (still big for me, I prefer less than 5") phone with a CPU that uses Cortex-A55 cores and UFS storage. Stuff inside it a giant 5000mAh battery. Let it charge at 0.8C or so. This thing will last for at least 2 days while also being decently powerful for everyday use. Gamers can have phones with C-A76 cores and some decent GPU along with an even bigger battery.
    Heck, size the battery this big and you could also have space to over-provision (scenario where you never actually use the full voltage range of the battery) and maybe double or triple the number of cycles it can run.
    Hey, a man can dream.
  • Drake H. - Tuesday, June 9, 2020 - link

    Agree. I would like a slightly smaller flagship, between 5 and 5.5 with thin edges, the current smartphones are too big to use with just one hand and do not fit in the pockets. As for SOC, I think Samsung has a low-end exynos(850?) that uses only A55, but it hasn't been released yet.
  • iphonebestgamephone - Tuesday, June 9, 2020 - link

    Cortex a55 actually uses more power at its max clcoks than a76 does at at its lower clocks.
  • Santoval - Monday, June 8, 2020 - link

    "What a lot of consumers however often misunderstand, is that these new fast-charging systems aren’t primarily enabled by new battery technologies, but rather by new advances in charging systems that have become more and more efficient."
    No matter how fast and efficient a charger is isn't the battery the ultimate limit? That's what's being charged. I feel that (super) fast charging solutions try to make Li-ion batteries behave like super/ultra-capacitors, forcing more and more power into them faster and faster. But they are not super-capacitors. They are batteries.

    Unless the batteries are designed to be a hybrid between super-capacitors and batteries, trading some energy density for more power density, making them behave like super-capacitors will just wear them down faster and faster. I hear the (upcoming?) solid state batteries will be the best of both worlds : they will have both a high power density (i.e. charging & discharging rate) and a high energy density.
    In the meantime the energy density of actual super-capacitors keeps on increasing, with the help of materials such as graphene. Perhaps the super-fast charging vendors should slow down until either of the above hits the market?
  • Sharma_Ji - Monday, June 8, 2020 - link

    Read the article, oppo anyways achieved.98% efficiency (it's on discharge cycle side though) by just using two batteries, if they are using this new tech, more efficiency during charging time also, just by new charger tech.
    Where's the need of battery tech.
  • iphonebestgamephone - Tuesday, June 9, 2020 - link

    A universal charger?
  • bobsmith1492 - Monday, June 8, 2020 - link

    Color me sceptical but switched capacitor power supplies have always been horribly inefficient with their only advantage being simplicity and part count.
    The problem is when you switch a voltage onto a capacitor it charges with high current for low esr caps like ceramics. The switches burn a lot of power doing so. There's a real limit to the maximum efficient. A buck regulator can approach 100%. You would need a buck regulator anyway to control battery charging. Curious what the benefit of this would be.
  • greenwoodin - Tuesday, June 9, 2020 - link

    I agree switched capacitor power supplies have always been horribly inefficient. The point of the article is that recent developments have shown switched capacitor power supplies that are incredibly efficient at fixed division ratios, A buck regulator can theoretically approach 100%, but you would need incredibly large inductors with extremely low DCR to achieve that. Under the tight space constraint in smartphones, switched capacitors can achieve much higher efficiencies ~98% than buck converters with ~90%.
  • DZor - Monday, June 8, 2020 - link

    Marketing!
    LiIon battery, whatever type it is, has 3 charging phases:
    1. pre-charge - slow till 20% charged
    2. fast charge - fast till cca 80% charged
    3. saturation charge - very slow till fully charged

    All fast charging is only in second phase and mobile phone will report full battery at some 80%. But it is not! Mobile phones, as electric cars, must take care of battery charge otherwise irreversible loss of capacity will happen.
    Most LiIon batteries have end charge voltage of 4.2V but depends. A bit more voltage, let say 4.5, destruction starts and at even bit more, let say 5v, battery might catch fire and explode.
    Charging efficiency in second phase is very high, 90+% but depends on charging current - higher current lower efficiency. Also, high charging rate results in lower life time.
  • ksec - Monday, June 8, 2020 - link

    Interesting but not a trade off I want. I want my battery to last longer. Fast Charging shortens its life by quite a considerable amount. For most people, I think battery capacity increase is a more important development.
  • hlovatt - Monday, June 8, 2020 - link

    The premise that the charger efficiency limits charging rate seems overstated. The battery limits the rate in two ways. 1. Charging damages the battery a little bit each time, the faster the charge the more damage. 2. The majority of the heat generated during charging is in the battery itself, not the charger, again the faster the charging the more heat. Whilst their switched capacitor technology might reduce cost and board space I doubt it makes much difference to the charge rate.
  • Andrei Frumusanu - Monday, June 8, 2020 - link

    Batteries don't heat up at all during charging, compared to the heat of the PMIC. It's a myth with no basis in reality. I've charged many disassembled phones with the battery outside the phone itself and it's not even lukewarm.
  • Sharma_Ji - Tuesday, June 9, 2020 - link

    True that, a real life example of that would be inverters that most of us have, the inverter gets pretty hot, while battery is barely hot to touch.
  • Lord of the Bored - Monday, June 8, 2020 - link

    " vendors have engaged in a literal arms-race"
    Boy, wouldn't THAT be an interesting market. But no, there is no LITERAL arms race going on, as charging circuits are only ever weapons on accident.
  • RICKIE - Monday, June 8, 2020 - link

    Lion semi is a pioneer in the field of Direct Charger IC. People want fast charging times, and they're solving it. May your business flourish.
  • zodiacfml - Monday, June 8, 2020 - link

    Well, avoiding heat while charging is welcome. I noticed this the first time with my S8+ which stops USB "slow" charging after minutes of video recording. Back then, I expected smartphones to have behave like laptop charging, basically, it will work with the adapter without the battery. It appears that phones don't directly get power from the adapter while plugged in.
  • greenwoodin - Tuesday, June 9, 2020 - link

    Exactly. Or if you are driving in hot weather with direct sunlight on your phone with navigation on, your phone will stop charging because it's too hot. I think this technology r just about fast charging; like you said, it's about reducing heat while charging so there is more heat budget for other stuff like processor overclocking.
  • iphonebestgamephone - Tuesday, June 9, 2020 - link

    Sony has a mode in which you can do exactly that, called hs power mode. You can also see if your existing phone has the circuitry for it by rooting and installing acc module.
  • wr3zzz - Monday, June 8, 2020 - link

    Where are we in terms of USB charger compatibility? I have had in two occasions where the proprietary charger got permanently "downgraded" after it was used to charge a phone using different system. Not only I had to purchase new proprietary chargers but now I am paranoid and essentially locking any proprietary “USB” charger to a single device.
  • greenwoodin - Tuesday, June 9, 2020 - link

    This is indeed an issue that will hopefully be solved with USB PD becoming more prevalent. But it seems like standards are always playing catch up to technology, so new tech keeps getting introduced before a standard is ready to support it.
  • PeterCollier - Monday, June 8, 2020 - link

    Does the Moto Razr also suffer from this 2% capacity loss from having two batteries connected in series?
  • greenwoodin - Tuesday, June 9, 2020 - link

    No Moto Razr only supports 15W charging, so it doesn't have the 2% capacity loss. The loss is only for phones supporting 65W charging, 4x faster than the Moto Razr.
  • Valantar - Tuesday, June 9, 2020 - link

    Interesting to get a look into these things, though IMO this has more value in higher power applications. Mind you, my phone (Motorola One Zoom) "only" charges at 18W, but at that level it gets what I would call lukewarm - no issue there. On the other hand, my Laptop - a Dell Latitude 7390 2-in-1 - gets so hot during charging that it's downright painful to keep on my lap, and even the keyboard area gets uncomfortably warm. That's when connected to a 65W 20V USB-C PD charger. There's clearly heaps of conversion loss in that system, of course combined with insufficient cooling of that area (the fan goes bananas when this happens, but it's on the other side of the chassis with no heatpipes or other means of transferring heat away from the power conversion area), but nonetheless it must be a disturbingly inefficient system given how hot it gets.
  • greenwoodin - Tuesday, June 9, 2020 - link

    Exactly. Even a 90% charger burns 6.5W in heat for a 65W charger, so it becomes incredibly important to improve the charger efficiency. Otherwise, your processor will keep throttling when the laptop is charging. It's counter-intuitive that the laptop gets slower during charging :)
  • greenwoodin - Tuesday, June 9, 2020 - link

    I've used Galaxy phones with 25W charging and moved to iPhone XS Max recently. I was stuck with the inbox 5W charger, so charging was incredibly slow (iPhones can get 18W if you buy the wall adapter). iPhones have longer battery life, but still I often run out of battery around 7pm, and it's very frustrating if I need to wait a long time to charge it, or have to sit next to a wall plug. I think it is more inconvenient because I've been used to fast charging for 10 min to get to around 30%, while in contrast it feels like iPhone charging is so slow. Like most features in a smartphone, you feel the pain much more when you get used to a feature and have it taken away.

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