[Merged] iPad Battery Life Impressions Thread

autopsytheclown

macrumors newbie
Original poster
Mar 30, 2010
19
0
ModNote: Please use this thread for discussion of iPad battery life impressions and related concerns.

When we get our precious little iPads, how much battery life will be available do you think? This is my 1st pre-order so for those who pre-ordered an iPhone might have an answer.
 

msduncan

macrumors 6502
Jan 27, 2010
498
0
When we get our precious little iPads, how much battery life will be available do you think? This is my 1st pre-order so for those who pre-ordered an iPhone might have an answer.
Can't we just plug them in and play with them while they charge? Not being snarky, but asking a serious question....
 

autopsytheclown

macrumors newbie
Original poster
Mar 30, 2010
19
0
Can't we just plug them in and play with them while they charge? Not being snarky, but asking a serious question....
Yeah that is what I am doing but was just curious what % people think will be available out of the box. Once I open mine I am checking it out for sure then I will sync it to iTunes and transfer my stuff over.
 

PBG4 Dude

macrumors 68030
Jul 6, 2007
2,644
1,809
I imagine they'd have to hold a decent charge if Apple workers are going to be pulling them from boxes and setting them up for customers (there's only so many outlets at the genius bar).
 

PBG4 Dude

macrumors 68030
Jul 6, 2007
2,644
1,809
Actually speaking of this - what's the full charge time when on and plugged into a wall (sleeping)?
Usually, Lithium Polymer (LiPo) batteries can be charged at a maximum rate of 1C, or 1 times their max capacity. A 1000mAH battery can be charged at a rate of 1000mA (1A). At this rate, a completely depleted battery would take roughly 1 hour to recharge. In reality, a LiPo can only be 80% discharged without killing the battery / seriously decreasing usable battery life, so a recharge should only take 45 minutes, in theory.

I don't know if Apple will allow the battery to recharge at 1C though because it might produce too much heat while the battery charges.
 

SebZen

macrumors 6502
Apr 12, 2009
360
0
Usually, Lithium Polymer (LiPo) batteries can be charged at a maximum rate of 1C, or 1 times their max capacity. A 1000mAH battery can be charged at a rate of 1000mA (1A). At this rate, a completely depleted battery would take roughly 1 hour to recharge. In reality, a LiPo can only be 80% discharged without killing the battery / seriously decreasing usable battery life, so a recharge should only take 45 minutes, in theory.

I don't know if Apple will allow the battery to recharge at 1C though because it might produce too much heat while the battery charges.
We're all engineers here and have a pretty good idea what you are talking about.
 

bluehaze013

macrumors 6502
Nov 23, 2007
340
0
Battery life?

Been using my iPad for about 3hours now and I'm down to 60% battery left so I'm guessing about 6-7 hours battery life constant surfing over wifi. How is everyone else doing with regards to battery life?
 

brock2621

macrumors 6502a
Jun 8, 2007
992
451
Kentucky
Been HEAVILY using since 9:40 and I'm at 68%. These new samsung chips are truly impressive.

EDIT: that's WITH location services, 15 min mail fetch and push notifications all on
 

Julien

macrumors G4
Jun 30, 2007
11,140
3,826
Atlanta
How on earth could battery life be determined today since it would need to charge several hours to insure a full charge (the last few percent are the slowest (trickle charge)):confused:
 

brock2621

macrumors 6502a
Jun 8, 2007
992
451
Kentucky
How on earth could battery life be determined today since it would need to charge several hours to insure a full charge (the last few percent are the slowest (trickle charge)):confused:
Mine came with 96%, took about 25 mins to fully charge
 

Diversion

macrumors 6502a
Oct 5, 2007
739
108
Jacksonville, Florida
I don't know how Apple did it.. but the battery life is insanely good. Been using mine on wifi, gps on, and push on for almost 4 hours now and only down to 78% battery.
 

bluehaze013

macrumors 6502
Nov 23, 2007
340
0
Been HEAVILY using since 9:40 and I'm at 68%. These new samsung chips are truly impressive.

EDIT: that's WITH location services, 15 min mail fetch and push notifications all on
Did you charge it to full first? Your battery life seems much better than mine...didn't charge mine all the way started at 97% perhaps it will be better once I drain it and recharge.
 

Julien

macrumors G4
Jun 30, 2007
11,140
3,826
Atlanta
Mine came with 96%, took about 25 mins to fully charge
Battery meters are not that accurate and you can't know for sure if it was a full charge. You would need to leave on charge for several hours to be sure all the cells were in fact fully charged.
 

iParis

macrumors 68040
Jul 29, 2008
3,662
26
New Mexico
Battery meters are not that accurate and you can't know for sure if it was a full charge. You would need to leave on charge for several hours to be sure all the cells were in fact fully charged.
Kinda right and kinda not. Just because the battery meter is full doesn't mean it's fully charged. But it is fully charged when the icon changes from a lightning bolt to a "charged" icon.
 

brock2621

macrumors 6502a
Jun 8, 2007
992
451
Kentucky
Kinda right and kinda not. Just because the battery meter is full doesn't mean it's fully charged. But it is fully charged when the icon changes from a lightning bolt to a "charged" icon.
The icon switched to a "plug" icon and the screen lit up. Messed with it for two more mins while plugged up and then unplugged it. I forgot to mention I also have the "Boy Robot - Rotten Cocktails" album playing in the background as well so I'm really stressing it.
 

iParis

macrumors 68040
Jul 29, 2008
3,662
26
New Mexico
The icon switched to a "plug" icon and the screen lit up. Messed with it for two more mins while plugged up and then unplugged it. I forgot to mention I also have the "Boy Robot - Rotten Cocktails" album playing in the background as well so I'm really stressing it.
Yeah, that's what I mean. Your iPad is definitely fully charged, even if it's playing music in the background. Once the battery is fully charged, the iPad draws the rest of it's power from the source it's plugged into and not the battery until it is unplugged.