This guest post was written by Joseph Davenport.
One of the hot-button issues concerning the HTC EVO 4G is the safety and value of trickle charging and the use of kernels that supposedly enable it.
In layman's terms, under normal charging your EVO charges to 100% and then the internal charger shuts off, forcing your phone to run off the battery instead of using power from the outlet or USB port on your computer. When you have a trickle charging (aka SBC) kernel, your charger stays on, continually feeding your battery a small charge after it hits 100%. This keeps your battery at 100%, instead of your EVO running off the battery and losing charge.
Although this sounds great, some believe that things that sound "too good to be true" usually are. So let's briefly discuss the two sides of the trickle charging argument.
One the one hand, you have a fully charged battery. This should be kind of obvious, but the reason that you want to trickle charge is that you'll have a battery that doesn't display the false 100% charge. Instead, you have a battery that is running at an actual 100% charge, which will extend your battery life.
On the other hand, you might turn your phone into a grenade. As some of the commenters in the previous trickle charging kernel post have pointed out, trickle charging is seen by some as being dangerous and at the very least potentially damaging to your battery.
So, you have the two schools of thought: those who feel trickle charging is the greatest thing since sliced bread, and those who think it’s the most dangerous thing you can do with your EVO other than attempt to eat it. But who is right?
In the end, you just have to feel comfortable about what you’re putting onto your EVO. Every person has their own threshold of risk that they are comfortable with. It’s the reason that there are some people who root their EVOs and flash everything under the sun (thanks, Nandroid!) and some who keep their EVOs bone stock.
I have used luisrcastillo and jsseidel's Savage kernel in the past on my own EVO (hardware 0002, CyanogenMod 6.1.2) with no ill effects. On the contrary, my EVO's battery life extended by at least a couple hours. I charge every night, so I'm not sure exactly how long. All I know is that every time I went to bed, my EVO showed in the green. Note: It seems that the Savage devs have pulled SBC off of their kernel for the time being, probably because of the mixed feelings about it. The versions (1.5.2 and 1.6) that I used, however both had SBC.
If you're still on the fence about what to think of trickle charging kernels on your EVO, then check out what was posted to the XDA Developers Blog the other day. Evidently, our EVOs were shipped with a hardware failsafe against overcharging past the battery's safety limits. You cannot remove or change the failsafe with a kernel. A quote from the author, egzthunder1:
"So, to all of you who assumed that the SBC kernels could indeed override this, as there is a hardware protection in place, the device cannot be overcharged or rather charged past its safety limits."
So with all that being said, SBC kernels, while controversial, are most likely safe.
There are always going to be isolated incidents where EVOs start to malfunction, but what we don’t know right now is the specific cocktail of circumstances.
But here’s some quick, one-hit advice if you’re going to use an SBC kernel: Don’t overclock your processor past 1.1Ghz. As we all know, SBC puts a strain on the battery, more stress than HTC originally intended to have put on it. Overclocking the processor unreasonably just adds to the strain.
Whatever you decide to do, please study up on it and make sure you know the risks.
This guest post was written by Joseph Davenport (J.D.), editor-in-chief of The Tech Councillor.