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Surface Laptop (Intel and AMD) vs M1 MacBook Air. Oh my...

44 minutes ago, leadeater said:

If laptops came with Power Cell batteries then current/wattage limiting wouldn't be a necessity but you would also have a lot lower run time on battery for lighter loads. Since the most typical is lighter loads the more suitable type is Energy Cell.

The behaviour while reaching the lower limit is not an excuse to throttle something across the entire capacity range. And larger batteries of the same type are actually more capable than lower capacity ones. I don't mind some throttling and power saving routines when the battery drops below 20%, but there is no technical reason to do these things all the time. It's a design choice, not an intrinsic battery characteristic.

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1 hour ago, HenrySalayne said:

The behaviour while reaching the lower limit is not an excuse to throttle something across the entire capacity range.

Well the problem is the voltage drop happens very quickly, even near full charge and as each cell drops in voltage the current output also drops and that has a knock on effect to other power regulators and DC to DC converters.

 

Most of these batteries in question are only capable of peak performance above 80% charge, not a problem if the device draw is actually below the capability.

 

AMD CPUs just haven't been in the market for very long, not in OEM laptops, so the polish and refinement Intel based products got over decades simply isn't there. The Surface Laptop is a good example of a bad implementation.

 

1 hour ago, HenrySalayne said:

not an intrinsic battery characteristic

Yes it is, Energy Cells are simply bad at this, that's why power tools do not use them. A device design to operate at peak at 14.4V is simply going to be unable to do the task if it's only ~11V. The difference in power and torque is very significant. Have a look at some Ryobi Impact Driver reviews using the 2Ah battery and the 5Ah battery, the different is huge even at 100% charge for both.

 

Same applies to mobile devices and is the direct cause of unexpected device reboots. Luckily this only happens after the battery degrades a bit but that can happen in less than a year depending on how much demand you put on your device.

 

Small lightweight devices just don't have the volume to put in proper resilient batteries. Edit: This is why power efficiency in laptops is actually important and why the M1 does so well comparatively as the mean and median power draw is lower than x86 CPUs of the same/similar TDP, the M1 does not have aggressive boost technology. An x86 CPU pretty much tries as hard as it can to always use as much power as possible all the time always unless the load is actually very low. An M1/ARM CPU (without frequency boosting technologies) will only use as much power as the workload necessitates, the TDP on the M1 is the upper max, the TDP on an Intel/AMD CPU is the typical/apparent power under load. Actually very different things.

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17 minutes ago, leadeater said:

Most of these batteries in question are only capable of peak performance above 80% charge, not a problem if the device draw is actually below the capability.

Where did you get this information?

You already provided graphs showing the battery behaviour. The voltage of the battery is basically dropping almost linear over time. Setting the minimum requirement for the battery at 80% capacity basically means it's unusable for the desired purpose.

And unlike capacitors which can supply quite high transient currents but need time to recover, batteries generally don't show this kind of behaviour. If the current draw is decreased the voltage will rise and follow the load basically without delay. Battery behaviour is quite close to a classic voltage source with an internal resistance.

 

25 minutes ago, leadeater said:

Same applies to mobile devices and is the direct cause of unexpected device reboots.

Transients are the reason for unexpected device reboots, not sustained current draws.

 

Sustained load shouldn't be an issue while transient loads are fine. That's why locking the turbo window while running on battery and unlocking it while running of the AC adaptor is just a design choice.

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21 hours ago, jaslion said:

I mean nothing unexpected here. The air isn't thermally limited in such short runs and it is current gen tech. Amd and intel stuff is last gen stuff already.

 

Still impressive for a arm chip and excited to see where it goes.

M1 is as last gen as is Ryzen 5000. They are both from about the same period (fall 2020).

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3 hours ago, maartendc said:

Interesting...

 

But really the speed at which apps open is more dependent on storage speed than CPU speed, isn't it? If you are comparing an NVME SSD equipped Intel Macbook vs an NVME SSD equipped M1 macbook, is the difference noticeable?

 

I own a 2019 Macbook Pro with Core i9 (9880H) and it has a blisteringly fast NVME SSD. So I wonder if I would notice much of an improvement, I wouldn't think so? Storage speed should be the same, and the i9 CPU can at least turbo up to very high clock speed momentarily while opening an app.

It's not about loading apps, it is the over all responsiveness when using the computer, switching between apps, switching virtual desktops, zooming in and out in pictures/documents/webpages. 

 

Everything feels "crisp" for a lack of better word (or "snappy" if you will). 

 

As I said it is hard to describe. 

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i mean it's a surface. Trash of line of products since the first one showed up back in 2012. MS should just can the whole lineup and focus on actually making Windows something useable. They suck at hardware, stick to software.

One day I will be able to play Monster Hunter Frontier in French/Italian/English on my PC, it's just a matter of time... 4 5 6 7 8 9 years later: It's finally coming!!!

Phones: iPhone 4S/SE | LG V10 | Lumia 920

Laptops: Macbook Pro 15" (mid-2012) | Compaq Presario V6000

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45 minutes ago, RejZoR said:

M1 is as last gen as is Ryzen 5000. They are both from about the same period (fall 2020).

But the Surface Laptop 4 still uses a 4000-Series Mobile Processor - which is still on Zen 2 architecture. Ryzen 5000 is Zen 3.

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18 hours ago, TheReal1980 said:

Don't know if anyone who posted in the thread watched the video but the AMD model had, in one test a reduction in performance of about 50% when running it on battery compared to charger, that is totally unacceptable.

I thought AMD would be this fantastic comeback of a company with great hardware but something feels shady.

Well the alternative is that they intentionally nerf the performance of their laptops on the charger. Obviously if you have a better power source and aren't power limited you will have higher performance. I for one wouldn't want AMD to nerf that performance simply because some are salty that it doesn't perform as well on battery. 

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16 minutes ago, Laborant said:

But the Surface Laptop 4 still uses a 4000-Series Mobile Processor - which is still on Zen 2 architecture. Ryzen 5000 is Zen 3.

Is the Single Score on Geekbench higher on a AMD 5000-series than the M1?

If it ain´t broke don't try to break it.

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I don't want Apple to win the PC space. Come on other companies! Bring the heat! But don't actually 😉

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14 minutes ago, TheReal1980 said:

Is the Single Score on Geekbench higher on a AMD 5000-series than the M1?

There it is at least a tie... between the Desktop 5000 variants and the Mobile M1. Which is devastating considering the difference in power draw.

Yes, the M1 still humiliates x86 - and I'm considering getting an M1 Mini (mainly to have a really snappy but totally silent Work-Computer. My Game-PC is not loud at all, but for 8 hours of programming... it gets annoying.)

After seeing the M1 as "Apple's first shot" humiliating x86 as a whole... I kinda ask myself, if AMD just pulled ahead of Intel because these were really sleepy boys... or if AMD is actually good (on x86).

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1 hour ago, Laborant said:

There it is at least a tie... between the Desktop 5000 variants and the Mobile M1. Which is devastating considering the difference in power draw.

Yes, the M1 still humiliates x86 - and I'm considering getting an M1 Mini (mainly to have a really snappy but totally silent Work-Computer. My Game-PC is not loud at all, but for 8 hours of programming... it gets annoying.)

After seeing the M1 as "Apple's first shot" humiliating x86 as a whole... I kinda ask myself, if AMD just pulled ahead of Intel because these were really sleepy boys... or if AMD is actually good (on x86).

Personally, I’m waiting for the M2/M1X to see where things fare. Apple first gen hardware always tends to be a lemon test.

 

That said, die shrinks aren’t going to get much smaller. 2nm is probably where it stops and other tricks will need to be employed until photonics catch up, and even then is only to reduce the thermal/energy consumption, it might not permit much faster speeds.

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6 hours ago, HenrySalayne said:

Setting the minimum requirement for the battery at 80% capacity basically means it's unusable for the desired purpose.

That's not what I mean, I mean the battery itself is only at it's peak performance at 80% and above. Electronics devices are designed with that in mind sure but the load demand they require doesn't mean they need that performance of the battery in the first place, that's not what I am saying. But what will happen is as you drop below 80% you are very quickly getting towards a point where the battery will not be able to provide the power for max all core boost. This further becomes a problem when the State of Health of the battery degrades over time, device design has to take in to account this not just it's day one maximum state of health.

 

6 hours ago, HenrySalayne said:

If the current draw is decreased the voltage will rise and follow the load basically without delay. Battery behaviour is quite close to a classic voltage source with an internal resistance.

That doesn't matter as the issue is under load, batteries do not recover load voltage when the load reduces. Unloaded voltage will be higher but this along with load voltage always goes down as a battery discharges, it will never go up.

 

6 hours ago, HenrySalayne said:

Transients are the reason for unexpected device reboots, not sustained current draws.

Correct and what do you think will happen when a battery with a Sate of Health of 75% at 70% charge that is only capable of say peak 2A for greater than 500ms need to supply 3A to the device when it enters high power mode, the device will crash. For this example the battery may have been able to do it at SOH 75% at 80% charge or SOH 90% at 70% charge. These figures are just an example but the problem is very real and electronic devices are and have been in the past limited by what our battery technology can do.

 

Laptop peak power is more frequent and longer than a phone, yes they have larger batteries and higher battery operating voltage but the limits of what batteries can do still apply.

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7 minutes ago, leadeater said:

Correct and what do you think will happen when a battery with a Sate of Health of 75% at 70% charge that is only capable of say peak 2A for greater than 500ms need to supply 3A to the device when it enters high power mode, the device will crash.

 

Laptop peak power is more frequent and longer than a phone, yes they have larger batteries and higher battery operating voltage but the limits of what batteries can do still apply.

That's what I'm trying to say here. It's not a capacitor, it's a battery. It doesn't matter if your pulling 3 amps for 2 seconds or 3 amps for 5 minutes. The voltage in both cases will be the same. If the device throttles after a few seconds of high load, it's not because of the battery.

 

21 minutes ago, leadeater said:

That doesn't matter as the issue is under load, batteries do not recover load voltage when the load reduces.

No, that's not true. If your pulling 2 A and switch to 1 A after some time, the voltage will rise to the 1 A load line. I hope my insane paint skills might clear up what I mean. 😅

grafik.png.cb5d170554916fd56ce902f8e2ffbd5b.png

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9 minutes ago, HenrySalayne said:

No, that's not true. If your pulling 2 A and switch to 1 A after some time, the voltage will rise to the 1 A load line. I hope my insane paint skills might clear up what I mean

Yes but that's still wrong to your point and you're reading the graph wrong for the issue btw.

 

The issue is when the load demand returns to 2A not drops to 1 A. Draw your line again but go from 2C to 1C then back to 2C again, notice how it's impossible for the 2C voltage to be higher than it was at the start? That's the problem.

 

Edit:

If max boost requires 2C discharge load then and discharge load below 2C isn't applicable to that load. If the device requires the cell voltage to be above say 3.2V for max boost i.e 2C then the only line on that graph that matters is the 2C line.

 

Also if I think what you might be wanting to get at is graduated performance throttling as the state of charge decreases then I agree that would be better I just don't know how possible that is. Most things are designed around acceptable worse/minimum cases not best case so if you can't do a graduated reduction then dropping down completely might be the only viable option.

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3 minutes ago, leadeater said:

Yes but that's still wrong to your point and you're reading the graph wrong for the issue btw.

That's a little bit harsh (and also wrong). My point still is (and always has been), that there is no point in throttling a sustained load, but allowing small full performance "turbo windows" while running on battery. And if the performance has to be throttled because of the voltage, it's only necessary when the capacity drops below 30% or something in this neighbourhood. That's exactly what the graph shows and that's exactly what I drew. If throttling isn't linked to remaining battery capacity, it's a design choice, not a necessity.

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That browser test is completely pointless if all the laptops aren't running the same browser.

But interesting to see the Ryzen version of the laptop being throttled, I thought the 4800U was more efficient than the Intel version, either a poor design decision from Microsoft or done so it has better performance on battery.

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3 hours ago, HenrySalayne said:

That's a little bit harsh (and also wrong).

Sorry, that wasn't meant as harshly as you took it.

 

3 hours ago, HenrySalayne said:

it's only necessary when the capacity drops below 30% or something in this neighbourhood.

Not necessarily. Neither of us know what that point is but it can easily be well above 30%. The voltage drop is significant at far higher charge capacities than this. I've seen Android phones crash and reboot at 80% charge and they were not that old either, just heavily used. To be fair that's a battery state of health issue primarily but it results in the problem I have described, the battery not being able to deliver the performance it once could and that does need to be considered when designing a product.

 

3 hours ago, HenrySalayne said:

That's exactly what the graph shows and that's exactly what I drew

I know what you drew but what you drew is not the graph for the CPU operating in 30W mode when boosting. You drew lines for the CPU operating in various different power modes, not the CPU that has a single high power mode over time. The CPU will go in to and come out of that power mode over time as the battery drains, there is only 1 line of the graph what would represent that mode.

 

What you drew is the CPU only ever being in the high power mode once, then never going back in to it again, which isn't how a device gets used.

 

What you drew is only possible if the CPU has multiple different boost power configurations which it doesn't, not easily anyway. There is the default cTDP modes of 15W and 25W and the default boost power of 30W. You can use Ryzen Master or other software to change parameters like boost duration and boost power limit but that would have to be active software monitoring the charge state of the battery and changing these over time, no good if the software isn't running or crashes or get uninstalled. I suppose it might be possible to do this more at a firmware level but that's also a lot of work to do that, maybe something Microsoft didn't want to do.

 

TL;DR A CPU isn't going to know what charge state a battery is and if it's boost state is 30W then it's going to boost to 30W every time, not some other value. Battery at 80% charge and CPU boosts, 30W. Battery at 50% and CPU boosts, 30W. Battery at 10% and CPU boosts, 30W.

 

3 hours ago, HenrySalayne said:

My point still is (and always has been), that there is no point in throttling a sustained load

Well I think the problem is the peak load is actually quite long. I think most of the tests are within the boost window so actually above 15W and actually 30W. I suspect on battery the Surface is not allowing the CPU to boost up to that 30W like it does when plugged in. The Asus ZenBook on the other hand does allow it on battery (I think).

 

Also I don't actually think the battery in the Surface is actually that bad it's required to disable the 30W boosting but I suspect Microsoft just didn't have enough confidence and knowledge in AMD hardware so took that approach. Intel has a really big mobile division and has been working with ODM/OEMs for a very long time so there is a lot of knowledge about their platforms and capabilities and ways to handle them, this is much less so for AMD.

 

I really don't know why Microsoft has done what they did, for battery run time or something else, but it's definitely not the best example of Ryzen Mobile U on the market.

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9 hours ago, HenrySalayne said:

That's what I'm trying to say here. It's not a capacitor, it's a battery. It doesn't matter if your pulling 3 amps for 2 seconds or 3 amps for 5 minutes. The voltage in both cases will be the same. If the device throttles after a few seconds of high load, it's not because of the battery.

 

No, that's not true. If your pulling 2 A and switch to 1 A after some time, the voltage will rise to the 1 A load line. I hope my insane paint skills might clear up what I mean. 😅

grafik.png.cb5d170554916fd56ce902f8e2ffbd5b.png

 

 

Here's the point thats going over your head i think.

 

Any battery pack has a finite limit on the number of amps it can supply regardless of charge state. As a battery discharges it's output voltage under any given amps worth of draw drops. Since power is; (amps * voltage = watts), this means once the voltage drops enough it cannot supply enough watts worth of total power to run in high performance mode because it needs more watts than the battery can deliver to do it.

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I have an M1 MacBook Air and one thing I'm surprised about is the DaVinci Resolve speeds; I use DaVinci Resolve and it runs well, but I didn't know it was that good

Main PC:  MacBook Air (M1, 2020), 8GB of RAM, 256GB of storage. Running macOS, maybe Solus if it gets ported

Workstation: Ryzen 5 1500X, 16GB DDR4-2400, ASRock B450 Gaming-ITX/AC, Optane 800P 58GB, Patriot Burst 240GB, Toshiba Q300 240GB, SAPPHIRE Pulse RX 570 4GB, beQuiet! SFX Power 2 400W, Silverstone ML08-B. Running Solus Linux and Windows 10

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OK, i'm not even gonna build this, but is this a good workstation?

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CPU Cooler: Corsair H100i 77.0 CFM Liquid CPU Cooler  ($168.99 @ Amazon) 
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Total: $1745.91
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2016-02-09 12:48 EST-0500

 

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7 hours ago, leadeater said:

TL;DR A CPU isn't going to know what charge state a battery is and if it's boost state is 30W then it's going to boost to 30W every time, not some other value. Battery at 80% charge and CPU boosts, 30W. Battery at 50% and CPU boosts, 30W. Battery at 10% and CPU boosts, 30W.

So you are telling me, the hardware can change the power envelope when I plug in an AC adapter, but is unable to change the power envelope depending on the battery charge left? 🤔 Seems like an arbitrary limitation to me. 😉

 

8 hours ago, leadeater said:

've seen Android phones crash and reboot at 80% charge and they were not that old either, just heavily used.

A dead battery is a dead battery, but that's not the point here.

1 hour ago, CarlBar said:

Any battery pack has a finite limit on the number of amps it can supply regardless of charge state.

Yes, but let's do a quick recap of this graph:

image.png.31ff41de6429b4587fc5721753f235ae.png

Usable battery capacity for supplying sustained 19.2 Watt (6.4 A * 3 V): 2300 mAh

Usable battery capacity for supplying sustained 9.6 Watt (3.2 A * 3 V): ~ 2850 mAh (+24%)

Usable battery capacity for supplying sustained 4.8 Watt (1.6 A * 3 V): ~ 3150 mAh (+10%/+37%)

 

Basically supplying 3.5 times more power decreases the usable capacity by 1/3.

We are looking at a single capacity optimized 18650 cell! I don't see why a notebook battery shouldn't be able to do something like 30 W. Taking into account modern phone batteries (4.000 mAh range) can be charged with 30 W, 40 W or sometimes even 60 W and it is a reversible process, much larger batteries shouldn't perform worse.

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4 hours ago, HenrySalayne said:

So you are telling me, the hardware can change the power envelope when I plug in an AC adapter, but is unable to change the power envelope depending on the battery charge left? 🤔 Seems like an arbitrary limitation to me. 😉

Yes, going between two different power profiles based on AC or battery is fairly simple, something that has been done for a rather long time now. Going between say 14 different ones is an entirely different thing. It's not arbitrary, in the past some values would only apply after a device reset as well. Remember just because you think something shouldn't be a problem or should be easy doesn't actually mean it is.

 

The issue isn't the ability to change based on battery charge level the issue is how many power states can actually be set, what can be changed, how you change it. If the only option is allow 30W boost or do not allow 30W then how do you propose allowing 20W boost when such a configuration isn't supported? Now I know you can in reality set any power limit you want but what is your proposal to actually implement this reliably and consistently?

 

4 hours ago, HenrySalayne said:

A dead battery is a dead battery, but that's not the point here.

No it is the point, batteries have a state of health and that directly relates to the performance i.e. it's ability to hold charge voltage under load and how much current it can supply both peak and sustained. You can't just wave your hand and say it's fine because at 100% SOH it is able to supply the device when you've made no consideration for when the SOH is 60%. My electric car SOH is 62% and is still perfectly functional because it wasn't designed around only being usable with a SOH of 100%, or 80% or some other unreasonably high value.

 

Batteries degrade and is a fact of life that is included in device design, some do better job at that than others.

 

Also no those batteries in question are not dead either, they can power the phone for many hours, what they can no longer do is power the device under a high demand mobile game that put the SoC in to the highest power state possible. For some of them it's as simple as turning the screen brightness down to very low and the device will no longer reboot, you can only work around that for so long however. Neither should a phone and it's battery only last for around 12 months either, but I know technology just isn't there to improve that for those more demanding users.

 

4 hours ago, HenrySalayne said:

We are looking at a single capacity optimized 18650 cell! I don't see why a notebook battery shouldn't be able to do something like 30 W.

Because it's 30W just for the CPU not for the entire device.

 

4 hours ago, HenrySalayne said:

Usable battery capacity for supplying sustained 19.2 Watt (6.4 A * 3 V): 2300 mAh

Usable battery capacity for supplying sustained 9.6 Watt (3.2 A * 3 V): ~ 2850 mAh (+24%)

Usable battery capacity for supplying sustained 4.8 Watt (1.6 A * 3 V): ~ 3150 mAh (+10%/+37%)

 

Basically supplying 3.5 times more power decreases the usable capacity by 1/3.

Couple of issues here, you're not taking in to account the required input voltage by the power delivery of the laptop to be able to supply the CPU with the correct vCore voltage and current. Like I said there is a cut off point to how low that can actually be, I don't know what that is as it's different for each device and could easily be some point above 3V cell voltage. I have a laptop that is only 3 Cells and I'd like to get more than an hour run time out of it and I'd also like it to not reset on me just because my battery is 50% charge and I wanted to do something that caused the CPU to go in to peak power mode and I also have my screen brightness at max and the fans at high RPM because the device is hot.

 

It doesn't matter how much usable capacity difference there is, if you look at my original point I said it's the cell voltage that can be an issue. It doesn't matter if you only lose 1/3 the capacity if it's simply not able to actually supply the device the power required.

 

4 hours ago, HenrySalayne said:

Taking into account modern phone batteries (4.000 mAh range) can be charged with 30 W, 40 W or sometimes even 60 W and it is a reversible process, much larger batteries shouldn't perform worse.

Charge and discharge are entirely different things please don't conflate the two. Also rapid charging isn't actually good for the health of the battery either.

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6 hours ago, CarlBar said:

Here's the point thats going over your head i think.

 

Any battery pack has a finite limit on the number of amps it can supply regardless of charge state. As a battery discharges it's output voltage under any given amps worth of draw drops. Since power is; (amps * voltage = watts), this means once the voltage drops enough it cannot supply enough watts worth of total power to run in high performance mode because it needs more watts than the battery can deliver to do it.

Yes this, one side having a capacity discussion and the other side is having a supply of power discussion.

 

Performance reduction on battery has been a thing for a long time now and from everything I know about batteries run time is not the sole reason for this.

 

Everything has a minimum required voltage to operate and that is independent of the battery cell technology and it's minimum allowed cell voltage. Just because a battery can safely go down to a particular voltage does not mean the device can operate with that. My inverter has a minimum voltage above that of the minimum allowed voltage of my battery string for example, I can never actually fully drain my battery string as the inverter shuts off before then.

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7 hours ago, HenrySalayne said:

Usable battery capacity for supplying sustained 19.2 Watt (6.4 A * 3 V): 2300 mAh

Usable battery capacity for supplying sustained 9.6 Watt (3.2 A * 3 V): ~ 2850 mAh (+24%)

Usable battery capacity for supplying sustained 4.8 Watt (1.6 A * 3 V): ~ 3150 mAh (+10%/+37%)

 

Basically supplying 3.5 times more power decreases the usable capacity by 1/3.

We are looking at a single capacity optimized 18650 cell! I don't see why a notebook battery shouldn't be able to do something like 30 W. Taking into account modern phone batteries (4.000 mAh range) can be charged with 30 W, 40 W or sometimes even 60 W and it is a reversible process, much larger batteries shouldn't perform worse.

 

I'll freely admit, i have zero clue what any of this has to do with the point under discussion. This isn't a discussion about the mAh of the battery, thats a meaningless statistic here. It's a discussion about what levle of power the battery can sustainable about after accounting for voltage drop from discharge and battery wear from long term cycling. Thats what they set the power limits based on, the worst case real world circumstances that you can expect to happen.

 

As for why no variable set. The complexity is one factor, the focus on long operating times for such devices is another. And the last is liability. No two batteries will wear exactly the same, any data you see on that is just an average. You'd need real world monitoring built into each laptop. Leaving aside the difficulty and extra power use associated with that. That means there's now important data stored on the laptop that if it gets deleted by some method, (i can think of several ways), could, (and probably would, "no data" would have to default to new battery assumption to allow for replacements), result in the battery getting too much pull applied, not only could this wreak the other hardware, it could cause the battery to fail in a possibly fire inducing fashion. The amount of litigation they'd face over that and the public backlash on the difficulty of replacing dead batteries as well just aren't worth messing with.

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@CarlBar@leadeater

You two are still missing my point here. Every commonly used lithium-ion battery will behave exactly like the example @leadeater supplied. Independent of age, design and other parameters. The maximum power capabilities of the battery while fully charged are always way higher than the capabilities while almost drained. Limiting the power draw independent of the battery level to a worst case scenario (battery almost drained and even including ageing) is unnecessary and just a design choice. Nothing else.

Batteries are generally neither magic mystical creatures nor forged in Mount Doom and some things like the current draw characteristics are well understood. The power draw difference between "battery mode" and "AC mode" is generally below 50%. A fully charged battery should easily be able to handle this, if it's able to run fine with a drained battery.

5 hours ago, leadeater said:

Going between say 14 different ones is an entirely different thing. It's not arbitrary

Funnily enough this is by definition arbitrary. Why 14? Just a wild guess? I certainly never mentioned more than the two already in place. 😉

5 hours ago, leadeater said:

Charge and discharge are entirely different things please don't conflate the two. Also rapid charging isn't actually good for the health of the battery either.

No, they are not. At least to my maybe a little bit rusty understanding of the electrochemical processes in these cells. But if you have additional information about this topic, I would love to expand my knowledge.

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