Evo 4G Battery life, 64hr? Apparently, its possible

[Bateluer]

http://www.androidpolice.com/2010/07/11/rooted-htc-evo-4g-users-use-setcpu-to-extend-battery-life/

For many people, the EVO is an excellent phone, but extremely weak battery life is a huge detractor. Now, however, always-helpful user Pingpongboss has posted some instructions over at XDA-Devs for how to use the SetCPU app to significantly increase battery life. How significantly? He estimates that he could get 64 hrs with the screen off on a full charge. Pretty impressive stuff. Before and After graphs:

Jeebus, best I've ecked from my Droid is around 28, and that was with minimal usage the entire time. Screen off, no texting/email/browsing, the phone sat on my desk the entire time until it hit 5%.

 

[boomhower]

They are underclocking the CPU to like 250Mhz, stupid. I use the OC widget and get 24hrs of light use and 12hrs of heavy use with little issue.

 

[MrX8503]

I don't think there's anything that EVO 4G users can do to get great battery life. You can go from bad to ok battery life.

 

[vshah]

fyi:

That’s SystemPanel, paid on the market. A free alternative is JuicePlotter, also on the market. Screenshots were taken with Drocap2.”

 

[vshah]

i did a test on my N1 when i first got it. went ~3 days with no use. unplugged monday morning and it sat on my desk till wednesday night

 

[Brian Stirling]

I don't think there's anything that EVO 4G users can do to get great battery life. You can go from bad to ok battery life.

I think HTC could offer a new firmware/software update that could reduce power use without underclocking and that could improve battery life by 10%-35%. Froyo being much cleaner and faster could permit underclocking and still allow better performance and that could result in a 10%-35% improvement. Put the two together and I could see a 50% improvement in battery life or perhaps even more.

I charge my phone once a day when I go to bed and when I do the charge level is usually between 50% and 70% (off charge for 16 hours). With the possible improvements listed about I could go 2 days on a charge. With my iPhone 3G I had trouble getting one day during the first month but as the 3G network got built out that problem went away and I was usually able to go 2 days on a charge.


Brian

 

[Hail The Brain Slug]

Still doesn't hold a candle to the 3GS with iOS 3, I was able to get 100+ hours per charge with mild use (About 5-7 hours actual use,the rest standby with screen off.)

 

[ManSnake]

New record for me, ~49hrs out of the EVO with moderate use.

 

[Brian Stirling]

Still doesn't hold a candle to the 3GS with iOS 3, I was able to get 100+ hours per charge with mild use (About 5-7 hours actual use,the rest standby with screen off.)

Well, if I didn't use the 3G very much I could get 3 days between charges but the charge level after 3 days would be really low and I didn't want to run it that low. I don't see the Evo going that long even with the updates I suggest are possible but you never know.

It's my opinion that phone makers are too concerned with making the phones as small and thin as possible and as a consequence opt for a battery that's too small or marginal. If the Evo had been packaged with squarish sides like the new iPhone the battery compartment could have been made about 20% wider. The kick stand limits the vertical size of the battery and without that the battery could be 25% taller. And, if they made the phone a silly mm thicker the combined effect would be a battery that's about 75% larger with only a single mm thicker case.

If you did nothing else to improve usability that would nearly double the useful lifespan of the battery. Now, if HTC could improve the efficiency with a firmware/software update combined with underclocking that Froyo might permit we could see perhaps 50% more lifespan. Combine a larger battery with tweaks to the firmware and you might see a net improvement in lifespan of more than 160% or a life span that's 260% of what it is now -- all for one mm thicker phone. If you kept the same thickness but made the other battery compartment changes I outlined the net improvement might be 50% from the battery change alone and 125% if firmware improvements were also figured in.

As I said before, I like the package design (not the antennae) of the new iPhone and the squarish sides permit a wider useful space inside the phone versus the tapered sides of the older iPhones and the Evo. If I were in the design shop I scrap the kick stand and open up the battery compartment to fit a larger battery. I'd make the phone at least one mm thicker resulting in a battery compartment large enough to hold a battery that's nearly twice the size or close to 3000mAHr.


Brian

 

[MrX8503]

I think HTC could offer a new firmware/software update that could reduce power use without underclocking and that could improve battery life by 10%-35%. Froyo being much cleaner and faster could permit underclocking and still allow better performance and that could result in a 10%-35% improvement. Put the two together and I could see a 50% improvement in battery life or perhaps even more.

A made up statistic to validate another made up statistic. I suggest you stop making crazy assumptions.

New record for me, ~49hrs out of the EVO with moderate use.

Moderate use != Airplane mode

 

[FallenHero]

They are underclocking the CPU to like 250Mhz, stupid. I use the OC widget and get 24hrs of light use and 12hrs of heavy use with little issue.

How is it dumb to underclock the phone when you aren't using it? You don't need it operating at full power 100% of the time.

 

[Bateluer]

How is it dumb to underclock the phone when you aren't using it? You don't need it operating at full power 100% of the time.

Most OC kernels do this, run at high speeds when the power is needed, when the phone sleeps, it downclocks.

Their test, while interesting, does kinda render the phone useless. Its screen was off, its CPU was downclocked, and it likely sat on a table the entire time. Not really useful like that, it becomes an iPhone 4: Pretty, but unable to do anything productive.

 

[Brian Stirling]

A made up statistic to validate another made up statistic. I suggest you stop making crazy assumptions.

Yes indeed -- I pulled numbers out of my *ss. OTH, those numbers are in line with what you can expect to achieve from the techniques I listed. The numbers for a larger battery, however, are not guestimations and are instead the simple scaling a larger battery provides.

The Evo is what it is and while I expect newer large display smart phones to eventually come with bigger batteries the only improvement we can expect from an already designed phone is through firmware/software changes. By changing the way the phones handles weak RF you can significantly effect battery life. Also, if improvements in the OS allow the phone uP to be under-clocked, as the iPhone uP has always been, you can gain still more improvement.


Brian