Quick/DashCharge -> more heat?

[TehhMiik]

Guys, quick Q. Does pushing more amps to your battery generate more heat?

[Cyracus]

yes

[TehhMiik]

Just now, Cyracus said:

yes

Perf. Thanks.

[Froody129]

More amps is more resistance and also the same amount of heat is being released in less time

[unknownmiscreant]

Quick charge generates more heat in  the phone than dash charge as quick charge provides 15v (ish) to the phone which is then stepped down to 3.7 in the phone. Dash charge connects the battery directly to the phone, so 3.7v is supplied directly to the battery. All the step down is handled in the charger. 

Edited January 11, 2018 by unknownmiscreant

[unknownmiscreant]

16 hours ago, huilun02 said:

Yes but Dash charge doesn't produce nearly as much heat because its the charger doing the heavy lifting to lower voltage.

True my dash charge wall brick gets hotter than the phone, another thing to note, is that dash charge fast charges no matter what you are doing with the phone, wheras quick charge reverts to 'normal' charging whenever the screen in on.

[Zodiark1593]

On 1/11/2018 at 8:19 PM, unknownmiscreant said:

True my dash charge wall brick gets hotter than the phone, another thing to note, is that dash charge fast charges no matter what you are doing with the phone, wheras quick charge reverts to 'normal' charging whenever the screen in on.

This is what I've noticed too. When monitoring the charging, the current remains locked at about 2 amps (which is honestly still quite fast). With screen off, the charge speed is quite obscene, 12v at 3 Amps = 36 watts!

 

My phone has a 4k mAh battery, so fast charging shouldn't affect it quite as grievously as a phone with a smaller battery.

 

One advantage of Fast Charge over Dash Charge is that higher voltages are easier to transfer over a given cable than higher amps. Fast Charge isn't picky about cables, while Dash Charge may not appreciate the thinner cables.

[unknownmiscreant]

4 hours ago, Zodiark1593 said:

This is what I've noticed too. When monitoring the charging, the current remains locked at about 2 amps (which is honestly still quite fast). With screen off, the charge speed is quite obscene, 12v at 3 Amps = 36 watts!

 

My phone has a 4k mAh battery, so fast charging shouldn't affect it quite as grievously as a phone with a smaller battery.

 

One advantage of Fast Charge over Dash Charge is that higher voltages are easier to transfer over a given cable than higher amps. Fast Charge isn't picky about cables, while Dash Charge may not appreciate the thinner cables.

Dash charge is NOT 12v. There is no charge control circuitry in the phone (well technically there is, but its bypassed in dash mode.) The max dash charge operates at is 4A cable current. I have observed up to 3.3-3.5 A with the screen on. However this is supplied at a max voltage of 4V. A fully charged lithium cell is 4.2V, however the charge current is throttled at 80% (roughly 4v.)

 

Dash charge only works with dash cables. There is a single connector behind the normal 4. The charger uses this to check if the cable is dash. The charger and the phone then communicate, and the phone monitors the battery temperature, voltage and charge current before requesting a certain voltage from the charger in the range of 3.3 to 4.3V. The cable check is required, as most USB cables are only built to handle 1.5A max. Dash cables double up the conductors for power delivery so it can carry twice the current.

 

Quick charge on the other hand uses higher voltages (higher voltages at 1.5A) to get round the cable limitation. I can't remember the specs exactly, but its in the region of 9-15v. The big issue with that however is the 9-15v needs to be stepped down to 3.3-4.3 for charging the battery. This creates a thermal limitation, so fast charging only occurs when the screen is off (again quick charge chargers communicate with the phone to determine the voltage that should be supplied.)

 

All up the current max acheivable is 20W (dash charge) quick charge may be rated for more theoretically, however in reality, thermal limitations decrease this to 15-18w (ish).

[Zodiark1593]

2 minutes ago, unknownmiscreant said:

Dash charge is NOT 12v. There is no charge control circuitry in the phone (well technically there is, but its bypassed in dash mode.) The max dash charge operates at is 4A cable current. I have observed up to 3.3-3.5 A with the screen on. However this is supplied at a max voltage of 4V. A fully charged lithium cell is 4.2V, however the charge current is throttled at 80% (roughly 4v.)

 

Dash charge only works with dash cables. There is a single connector behind the normal 4. The charger uses this to check if the cable is dash. The charger and the phone then communicate, and the phone monitors the battery temperature, voltage and charge current before requesting a certain voltage from the charger in the range of 3.3 to 4.3V. The cable check is required, as most USB cables are only built to handle 1.5A max. Dash cables double up the conductors for power delivery so it can carry twice the current.

 

Quick charge on the other hand uses higher voltages (higher voltages at 1.5A) to get round the cable limitation. I can't remember the specs exactly, but its in the region of 9-15v. The big issue with that however is the 9-15v needs to be stepped down to 3.3-4.3 for charging the battery. This creates a thermal limitation, so fast charging only occurs when the screen is off (again quick charge chargers communicate with the phone to determine the voltage that should be supplied.)

 

All up the current max acheivable is 20W (dash charge) quick charge may be rated for more theoretically, however in reality, thermal limitations decrease this to 15-18w (ish).

I was referring to Qualcomm's quick charge when I mentioned 12V, as well as the specified (maximum) output of my own charger (not what my phone can take either). Would have helped had I specified beforehand I suppose 

[unknownmiscreant]

5 minutes ago, huilun02 said:

The Dash charge cable is a unique 7 pin design, has two more wires to transfer power compared to regular charging cables. Also its designed to withstand the rated high amperage output of the charger.

Check these out:

Cable:

http://www.chongdiantou.com/wp/archives/1672.html

Wall brick:

http://www.chongdiantou.com/wp/archives/1228.html

Car charger:

http://www.chongdiantou.com/wp/archives/1339.html

 

Theres some XDA and oneplus forum threads discussing it as well.

https://forum.xda-developers.com/oneplus-3/accessories/dash-charge-protocol-analysis-t3431917

 

https://forums.oneplus.net/threads/what-is-the-oneplus-3-dash-charging-sync-cable-doing-internally-lets-probe-it.456017/

[unknownmiscreant]

2 minutes ago, Zodiark1593 said:

I was referring to Qualcomm's quick charge when I mentioned 12V, as well as the specified (maximum) output of my own charger (not what my phone can take either). Would have helped had I specified beforehand I suppose 

Oh okay. I don't think it gets that high TBH though. Although I have never owned a QC3.0 (is there a newer version) phone.

[Zodiark1593]

Just now, unknownmiscreant said:

Oh okay. I don't think it gets that high TBH though. Although I have never owned a QC3.0 (is there a newer version) phone.

By my estimates (20%-90% within an hour on a 4k mAh battery), about 10-12 watts would be a reasonable assumption. Though I wonder how accurate the 3 amp (@12v) output rating on my charger is, assuming I could even find a Quick Charge 3.0 compliant device that could make use of that.

 

My device doesn't get all that warm either tbh unless I'm running the hotspot. In a confined area (covered by a pillow or other stuff), lukewarm is about as hot as it gets. Maybe device manufacturers can choose how aggressive they want to be with voltages.

[unknownmiscreant]

1 hour ago, Zodiark1593 said:

By my estimates (20%-90% within an hour on a 4k mAh battery), about 10-12 watts would be a reasonable assumption. Though I wonder how accurate the 3 amp (@12v) output rating on my charger is, assuming I could even find a Quick Charge 3.0 compliant device that could make use of that.

 

My device doesn't get all that warm either tbh unless I'm running the hotspot. In a confined area (covered by a pillow or other stuff), lukewarm is about as hot as it gets. Maybe device manufacturers can choose how aggressive they want to be with voltages.

Yeah the chargers can output between 5 and 20v in 0.1v increments. The output votlage is varied thorughout the charging cycle its based off device power draw, battery voltage, thermals and a few other things in all likelihood. So yes, manufactures can definitively choose how hot devices get. My OP3 charging at 3.3A gets hottish (near or a little over body temperature) in open air although the wall brick gets hotter. Under a pillow it cooks within 2mins, and can get quite hot while watching youtube videos while charging. 

 

As for the current rating, I'd say the charger can output 5v 3A or 12V 1.5(ish) amps. I think the max QC3.0 is rated to is 18w, although most devices struggle to make full use of this due to thermals.

[Zodiark1593]

2 hours ago, unknownmiscreant said:

Yeah the chargers can output between 5 and 20v in 0.1v increments. The output votlage is varied thorughout the charging cycle its based off device power draw, battery voltage, thermals and a few other things in all likelihood. So yes, manufactures can definitively choose how hot devices get. My OP3 charging at 3.3A gets hottish (near or a little over body temperature) in open air although the wall brick gets hotter. Under a pillow it cooks within 2mins, and can get quite hot while watching youtube videos while charging. 

 

As for the current rating, I'd say the charger can output 5v 3A or 12V 1.5(ish) amps. I think the max QC3.0 is rated to is 18w, although most devices struggle to make full use of this due to thermals.

Well, thermals and the battery probably wouldn't appreciate much faster than 1C charge rates anyway.

 

My device is pretty aggressive on the throttling, so even under load, it remains just warm. Gaming performance is notably much better during winter as an interesting side effect.

[Nena Trinity]

Yes but its done quicker so scientists are still not convinced its more or less harmful than slow chargers.