HTC Confirms to me Slow Charging on Froyo was designed on Purpose

[drako]

I wouldn't concern yourself with the current rating on car chargers vs AC adapters. These days, the charge circuitry (and most importantly, the charge controller) is located inside the phone - the adapter simply serves as a constant voltage source. They both downconvert to 5V and let the phone do the rest. The reason this is the case is because temperature is an input to the Li-Ion charge algorithm, and this is a safety feature. Each cell phone Li-Ion battery has a temperature sensor on it, which the charge controller uses to regulate the charging process. Basically, if the battery gets too hot, it 'splodes (starts releasing hydrogen gas and then finds an ignition source). While I don't know for a fact, there has to be some sort of limit on discharge as well, because its a safety thing.

The slow charge is no doubt HTC battery engineers being allowed to be battery engineers - they'll always go for slowest charge if they can because it's easier on the battery and extends its life (as in # of charge/discharge cycles over its life, not the life of an individual charge). C/10 is a number I typically hear, although that would mean a 10hr charge. Sounds like this is probably a C/5 or some such. Course, its annoying for the rest of us (but hey, we buy less replacement batteries).

And my understanding (although not 100% sure of this) that he heat-up during nav is the mostly due to the heat from the GPS receiver. Yes it will heat up the battery, being as everything is in close proximity.

 

[drako]

Oh, and the current rating on the chargers simply state how big the fuse is. The phone will draw what current it wants to draw - if the fuse can't handle it, it blows. And a C/5 charge on an 1150 Ah battery is 230 mA - well below both 1A and 500mA ratings.

 

[sabrewings]

Oh, and the current rating on the chargers simply state how big the fuse is. The phone will draw what current it wants to draw - if the fuse can't handle it, it blows. And a C/5 charge on an 1150 Ah battery is 230 mA - well below both 1A and 500mA ratings.

Incorrect, at least on the fuse part. The rating is what the maximum available power that can be provided is, as limited by the conversion hardware inside. There may be a fuse, but trust me in that I've exceeded the ratings of these same type devices several times and the only thing that happens is the voltage starts to drop off (conversion can't keep up with amperage so voltage has to suffer to maintain the max wattage). No fuse blows.

Back on 2.1, I use a special rig I built out of an old USB cable and some spare multimeter leads I had. The Inc would pull right up to about 960mA from the OEM wall charger.

Also, C/5 doesn't apply here since the battery doesn't take 5 hours to charge. It will charge inside of two hours, at least it did on 2.1. That translates to 845mA (assuming stock battery size as well as the 1.3 input-to-retained ratio of Li-Ion/Polymer).

Think of it this way. If what you said is true then charging off USB should be the same as charging from a wall charger, right? USB tops at 500mA so all is good. But, ask anyone who was used to the OEM wall charger and tried to do a full charge off USB and you'll find it took nearly twice as long (four hours to charge a phone, holy crap it was slow).

 

[drako]

Admittedly, C/5 was a WAG. I don't remember my phone ever taking 2 hours to charge, it was often more like 4+, I've always used a wall charger, and I have the stock battery. Did not know about the USB current limitation... I'd just assume not have to have a computer switched on to charge my phone (esp since I do it overnight). And yes, I know trickle-charge is bad, but better than having to deal with a phone tethered to a wall 4 of my waking hours.

 

[sabrewings]

The phone doesn't trickle charge at all. When it reaches full and the light goes green, the current into the phone stops. It effectively switches back to battery power.

 

[drako]

Wow, really? Ok, they really DID let the battery engineers go nuts! Certainly explains why bump charging in the morning takes 45 minutes.

 

[ORRY?]

I've got a 12VDC usb adaptor connected to a USB cord that I bought at a local grocery store. It can provide a max current of 1000mA per USB port, according to the packaging. I poked around on the internet to see if I could spot the same one, but came up empty. My 2 1/2 hour nighttime charge is usually done on my old Blackberry cord, which only goes up to 700mA.

Think you can buy that same exact charger from your local grocery store and send it to me? I'll pay you, of course

 

[tbdaly]

So does that mean we can not charge our phone while using our navigation???

Honestly, I think it depends solely on your device because i have not noticed any battery drain at all while using the nav. option on my phone, sure it gets hot but it did that before also. Also, it helps to turn the screen off when you're on a stretch of road that you know you won't be turning of off anytime soon, just a tip.

 

[funkpod]

Well, I drive from pennsylvania to vermont today, running gps from basically 9:30 this morning to about 6 pm, and aside for about 2 hours, had it plugged in all day. I was down to 2%, starting from 70%. This stinks. I even had my dc to ac car converter and my htc wall charger charging all day. The battery sstatus said ac charging. Fortunately I had spare batteries, so I could still use my phone. ANY suggestions?