• fonix232@fedia.io
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    9 days ago

    Pretty much every modern piece of USB-PD equipment supports bypass charging… What killed your Pico’s battery is most likely the heat not the possibility of there being no “bypass charging”.

    • Hond@piefed.social
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      8 days ago

      Ney,

      bypass charging isnt even nearly as widespread as you make it out to be. There are news articles written when a big phone manufacturer finally updates a device to support it. IMHO usb-pd is the same mess like with everything when it comes to usb standardization.

      Pico 4 batteries are in the back like with the frame. Sure charging also causes heat. But i doubt my pico batteries degraded because of their charging management beeing so bad that it causes heat death. thats just ridiculous.

      • fonix232@fedia.io
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        8 days ago

        “finally update a device to support it” are… are you seriously that dumb to think that a SOFTWARE update somehow “enables” a physical function?

        Look into how PMICs and BMSes work internally and how the power flow looks when running from battery vs when running from external power. Quite literally in the latter case, power cannot flow from the battery to the power rails because it’s being charged, and when the battery is fully charged, power is cut off. That IS the definition of “bypass charging”.

          • fonix232@fedia.io
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            8 days ago

            Holy shit are you mentally challenged. This is the very same PMIC feature I was talking about, and it wasn’t “enabled” period, but enabled WHEN USED IN CONJUNCTION WITH THE 80% CHARGE LIMITER. Very important distinction. Doesn’t mean the Pixel phones weren’t doing bypass charging prior to this.

            But of course to realise that you’d need some comprehensive reading abilities which you clearly lack.

            • Hond@piefed.social
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              7 days ago

              Uuuuuh, buddy…

              Getting so worked up over semantics of bypass charging isnt a good look fou you.

              Especially if you automatically treat people like they’re soo much dumber than yourself.

              Nothing wrong with sharing some knowledge and while doing that correcting people if they’re wrong.

              But i even looked up power management integrated circuits and battery managment systems. Idk but those arent even usb-pd or bypass charging specific things. Idk whats your point with that? Like that they exist and a 2026 high tech device will have them so the battery doesnt explode? Like, no shit?

              Happy to see some sources that bypass charging is basically a requirement with USB-PD.

              PS Fuck You

              • fonix232@fedia.io
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                7 days ago

                Well, since you’re so nice telling me to fuck myself while asking me to teach you, I’ll do just that, you dumb little shit. So sit down and shut the fuck up.

                Batteries can do two things, both exclusively, meaning the two can’t happen at the same time:

                • charge
                • discharge

                Energy either goes into the cell (charging) or goes out of the cell (discharging). The two literally can’t happen at the same time, due to the fundamental laws of physics, how electrons behave within the mediums inside a battery cell.

                Now that we cleared up, let’s discuss how a BMS works. A battery management system, as the name suggests, manages a battery. This is important because the lithium ion chemistry isn’t exactly stable, and thus you need to manage it. Like I’m managing all this information for you, you vapid cunt.

                So what a BMS does is ensuring that the cell neither goes below a safe voltage (over-discharge), nor does it go above (over-charge), nor does the cell pull or deliver too many amps (overheating issues). As I said, it manages the battery. A BMS is essential in any lithium ion battery application, let it be a phone, an UPS, battery wall, electric scooter/bike/car/airplane/boat, even shitty little RC cars and drones.

                Now, the BMS itself handles what you call “bypass charging”, aka not charging the battery beyond its safe voltage, cutting off the power supply to the cell when the right voltage is reached so the cell isn’t under active use. Every single BMS since the mid-2000s does this for safety reasons. Every. Single. BMS.

                So how this works is, the device by default is powered by the battery, the BMS pulling voltage from the cell and providing it to a number of power rails (via converters, let them be buck, step-up or step-down or any other configuration, even voltage dividers - feel free to look these terms up, there should be simple enough explanations that even an absolute doughnut like you can understand). Most devices will have a 5V, 3.3V and 1.8V rail for various applications (most “internal peripheries” like storage chips and sensors require 3.3V, external devices usually use 5V, and SoCs, other core chips use 1.8V). In some cases the 5V rail might not be the main one, but 3.3V, they’re freely interchangeable in this though exercise. The point is, there’s a primary rail, which will provide power to the rest - and it’s usually the highest voltage rail as it requires the lowest amps to deliver higher wattage.

                So the battery is nicely chugging along, then suddenly external power is connected. What happens will surprise morons like yourself:

                • USB-PD negotiates voltage
                • 5V rail is then powered by the external source, either directly or by conversion
                • other rails are now supplied by the 5V rail
                • this triggers the PMIC to signal the BMS that it can begin charging
                • BMS detaches battery from the outgoing power rails, ending the discharge cycle
                • BMS takes incoming voltage, steps it down to appropriate charging voltage (usually around 4.2-4.3V), and monitors the battery while it charges, limiting current as and when necessary
                • system is now powered via external power

                This is all neat, so where does “bypass charging” come in? Well quite simple, my dear simpleton, it happens when, quelle surprise, shocked Pikachu face - the battery is fully charged.

                See when the BMS detects the battery is charged - by the fact it reports an internal voltage of appropriate volts - it simply cuts off power to it. Charging voltage is dropped to 0, the battery is essentially disconnected (not fully physically, as there’s no internal relay inside, but a similar electric gate does stand in the way, disconnecting the cell from the rest of the circuit), and aside from voltage monitoring at an interval, the battery is idle. It’s not charging, it’s not discharging, it’s just sitting there, fully charged. All the while, the system is powered by the external power supply. The only reason the battery is not fully disconnected is so the battery can kick in the moment external power is removed so your system - whatever it may be - doesn’t get interrupted. But up until then, there’s no charge or discharge happening to the battery.

                Oh, and to cover that firmware update change: most modern devices (emphasis on most) use programmable BMSes where the charging voltage (which, again, microbrain, determines the charge status of a battery) can be set. So instead of 4.2V, which is 100% capacity, it can be set to around 4.12V (which is about 80%, well, approx. 78% actually), so the “bypass charging” cutoff happens there.

                Now, would you kindly stop swinging that microdick around and put it away before you prove to even more people just how stupid you are?

                • twix@infosec.pub
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                  7 days ago

                  Thank you for this. I understand your point, learned a few things and admire your energy. I hope your frustrations are superficial and don’t impact your general mental well being… Cheers :)

                  • fonix232@fedia.io
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                    7 days ago

                    My frustration is primarily with idiots who can’t explain themselves well while thinking they know better and are unable to accept when corrected. You, madam/sir, are of no cause for such.

                    I’m glad my writeup helped understanding this topic, even if on a surface level! I could get into the very specifics but if I’m going to write that much, it’s gonna be smut so at least I can make some money off of it.

                • Hond@piefed.social
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                  7 days ago

                  NGL,

                  this is a masterpiece of a post. Bravo. Perfect energy.

                  Still i think you are way to focused on the semantics. English certainly isnt my first language and with that i dont have any authority to judge how bypass charging is exactly defined. But that androidauthority article and many others pretty much use it to describe either a more intelligent battery management to improve battery health in the long term or/and to bypass the battery to directly power the hardware for heatmanagement. Samsung does the latter for its gaming mode on certain smartphones.

                  So your post is correct. But is still besides the point.

                  I absolutly take the blame for not beeing specific enough in my original post. But i feel like it was kinda implied that i meant the charge bypass which improves battery health in the long run edit: when the device is constantly or very often plugged in(which can be bad in the long run when the lion cells are constantly at 100%(i know its not really 100%)).

                  • fonix232@fedia.io
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                    7 days ago

                    I literally just described, in the most layman’s terms possible, how the BMSes of modern phones of at the very least the past decade have already been doing battery bypass. The laws of physics LITERALLY don’t allow for any kind of “non-bypass” approach. If you still can’t comprehend that, I’m afraid you might truly be a clinical case of mental retardation.

                    Again: what hurts li-ion cells is staying under voltage (i.e. being charged even at 0.000 amps) when fully charged. It’s not optimal for storage to be 100% charged and not used for a long period as the full capacity means higher self discharge rate thus more cycle usage thus (slightly) quicker degradation of the cell, but that doesn’t matter when the battery is regularly used and the 100% storage isn’t happening continuously for months at an end.

            • Shayeta@feddit.org
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              7 days ago

              If a feature is present, but not being used, that is effectively the same as it not being present in the first place.

              • fonix232@fedia.io
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                7 days ago

                It’s not about a feature “being present but not being used”. BMSes provide “bypass charging” by cutting off the battery once it’s charged so it’s not being used (neither charged nor discharged). This usually happens at the 100% charging voltage.

                Programmable BMSes allow this voltage to be set. When you limit battery charging to 80%, programmable BMSes allow the bypass charging to happen at this lower percentage, which simply wasn’t a default on Pixel devices because Google overlooked the connection between the software feature and the hardware control.

                This doesn’t mean that:

                • other manufacturers overlooked it too
                • the feature didn’t exist in the past
                • the feature didn’t work in the past
                • the feature is something new

                yet again, some reading comprehension of the full article instead of thinking you’re all-knowing because you’ve read the title or maybe even the first paragraph, is a super helpful skill in life. I recommend you start using it.

                • dil@lemmy.zip
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                  7 days ago

                  The issue is that they were confidently wrong, and you came off aggressive, ppl are just gonna look at tone and assume you’re wrong lol

                  • Shayeta@feddit.org
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                    6 days ago

                    Absolutely correct. I skimmed over the conversation and just replied with a vaguely correct sounding but poignant statement despite having 0 knowledge on the subject.

                    This is why it’s important to not invest too much of yourself in online discussions - people are stupid, especially people like me.