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[Lemurnator]

I got my iRiver H320 the other day and from what I understand the battery life is 16 hours yet when I charged the device for the first time I let it charge for good 45 minutes (before it was done) then removed it from charging to show it to a few people. From what I was told (from someone who likes to draumatize a little bit) you need to let Li-Poly batteries charge all the way or it would forever only charge to the point where it stopped charging the first time. In this case that's less than halfway. Is there any truth to this?

Also, does the iRiver suck juice out of the battery when music isn't playing and the screen isn't on but the unit is in sleep mode. IE: Being in a menu screen and letting it sit for a while.

I was making transfers from my PC to my iRiver earlier and the unit wasn't on for more than an hour or two. Connected to the USB port of my laptop. Next I looked the battery meter was at half way. Are battery issues a big problem with HD MP3 players or is that just the iPod?

 

[Mike Works]

Didn't you just make a thread about your mp3 player a couple days ago?

 

[Mr Gump]

Id suggest not throwing it into a raging fire. Yeah, dont do that.

 

[Lemurnator]

About the MP3 player. This about battery issues. I'd like to know this about rechargable batteries in general.

 

[way more]

That's false, just becasue that guy doensn't know what the fuck he's talking about. What you don't want to do is have it charged all the time becasue the battery will lose it's potential, and that my not even be true.

 

[Lemurnator]

Person who told me that is my dad and he's an electrician.

 

[tedtropy]

Person who told me that is my dad and he's an electrician.

What he's referring to are memory plateaus in the battery, something modern LiIon batteries don't really suffer from. It used to be a problem in older batteries, but I honestly wouldn't worry about it these days...

 

[fart]

deep cycling (fully draining) li-ions is bad. they don't have much in the way of memory otherwise. keep them topped off (fully charged) for longest life.

 

[cubicle47b]

I was making transfers from my PC to my iRiver earlier and the unit wasn't on for more than an hour or two. Connected to the USB port of my laptop. Next I looked the battery meter was at half way. Are battery issues a big problem with HD MP3 players or is that just the iPod?

The largest drain on your battery is accessing the hard drive. Your battery should last around 16 hours while playing MP3s (the percentage of time you're hitting the hard drive is very small) but copying files to it is going to drain it extremely quickly.

 

[DJ Sl4m]

copying files to it is going to drain it extremely quickly.

IAWTP

 

[maharg]

What he's referring to are memory plateaus in the battery, something modern LiIon batteries don't really suffer from. It used to be a problem in older batteries, but I honestly wouldn't worry about it these days...

What he said. Nickel Cadmium (the oldschool rechargables -- NiCad) had horrible memory problems where if you didn't charge them fully, they would basically have a complete, but temporary, drop in voltage at that point after recharging again. Some devices can be smart enough to deal with this, but it means keeping enough charge to cover the gap in the battery's life.

Nickel Metal Hydrate (NiMH) batteries have the same issue, but the gap is much much smaller. Small enough that most devices just notice a temporary drop in voltage, but not long enough to shut them down.

Lithium-based (Li, LiIon, LiPoly) rechargables basically don't have memory at all, but their lifespan is much shorter. Basically, they lose about 20% of their capacity level a year at room temperature. That can be mitigated if you store them cold though. At 0C, they only lose 6%/year. However, they only lose about 1/4 as much charge while idling than the Nickel based batteries.

[note: some of what I said above about memory is probably somewhat incorrect. I am not an engineer, I just play one on the internet: http://www.repairfaq.org/ELE/F_NiCd_Memory.html]

 

[gblues]

Memory was only ever a problem in NiCad batteries. Neither NIMH or LiION batteries have a memory. The most common cause of loss of battery capacity is using a shitty charger that over-charges the battery. Things like deep cycling can reduce battery life, too.

But you didn't screw anything up by only partially charging it. That's just an urban legend.

Nathan

 

[Fresh Prince]

Doesn't it charge while it is connected to USB or whatever she's using?

 

[nitewulf]

deep cycling (fully draining) li-ions is bad. they don't have much in the way of memory otherwise. keep them topped off (fully charged) for longest life.

seriously?
can you point me to some info on that? prefferably technical.

 

[Fresh Prince]

Here nitewulf:

http://www.batteryuniversity.com/parttwo-34.htm

http://www.batteryuniversity.com/partone-12.htm

 

[Crazymoogle]

Here nitewulf:

http://www.batteryuniversity.com/parttwo-34.htm

http://www.batteryuniversity.com/partone-12.htm

^One of the best documents online about Lithium-Ion batteries, and it pretty clearly makes the case that keeping your battery maxed out is a bad idea longterm.

The "rumors" and "advice" earlier in the thread are mostly about Nickel Cadmium (Nicad) batteries or variations thereof, which can suffer from memory effects and such.

 

[nitewulf]

hmm, thanx.

 

[fart]

right, if you're going to remove it and store it you want to keep it as cold as possible and at about half charge, otherwise you want to avoid cycling it. hence, keep it topped off in usage situations. the problem with an mp3 player is that you CAN'T REMOVE IT TO PUT IT IN A STORAGE SITUATION. so stick to not cycling it doofus

 

[nitewulf]

right, if you're going to remove it and store it you want to keep it as cold as possible and at about half charge, otherwise you want to avoid cycling it. hence, keep it topped off in usage situations. the problem with an mp3 player is that you CAN'T REMOVE IT TO PUT IT IN A STORAGE SITUATION. so stick to not cycling it doofus

the articles werent clear on whether a 30% or 40% recharge would be considered a cycle though.
say you can recharge 300 times, you charge it once initially, and use it for 4 hours daily thereby draining 40% of max charge. and then you recharge daily, so each recharge would decrease the charge count or not?

 

[maharg]

^One of the best documents online about Lithium-Ion batteries, and it pretty clearly makes the case that keeping your battery maxed out is a bad idea longterm.

The "rumors" and "advice" earlier in the thread are mostly about Nickel Cadmium (Nicad) batteries or variations thereof, which can suffer from memory effects and such.

Maybe, you know, read the thread before talking about the 'rumors' and 'advice' it contains. Pretty much everyone said her dad was full of it and thinking of the wrong type of batteries. Not a single person said anything along the lines of what you said they did.

kthx.

 

[fart]

the articles werent clear on whether a 30% or 40% recharge would be considered a cycle though.
say you can recharge 300 times, you charge it once initially, and use it for 4 hours daily thereby draining 40% of max charge. and then you recharge daily, so each recharge would decrease the charge count or not?

i think the cycle count thing is arbitrary. i know for ibm batteries, a discharge to 85% or below and then a recharge is a full cycle. however, a shallower cycle probably wears less on the battery than a much deeper cycle. this is where you have to have a deeper understanding of battery chemistry and management electronics though, so i really don't know. i'm pretty sure everyone considers a discharge to 40% capacity a cycle though.

the point is not to treat it like a nimh or nicad where deep cycles were recommended to avoid any memory effect, since there's no memory effect, and deep cycling damages the cells

also, if it's not clear, doofus wasn't referring to you.

 

[Crazymoogle]

Maybe, you know, read the thread before talking about the 'rumors' and 'advice' it contains. Pretty much everyone said her dad was full of it and thinking of the wrong type of batteries. Not a single person said anything along the lines of what you said they did.

Except for, you know, the thread starter. Whatever, the main point is that the link is great. My apologies if you took that the wrong way. Anyways...

fart: Cycle count is pretty arbitrary, but with smaller portable devices I get the impression that 20% is the magic number for a full cycle (and wait, it's sort of backed up by this).

From personal experience, current draw can also have a noticeable effect on battery lifetime - ie: a laptop with a 17" LCD burning a DVDR would probably hurt the internal chemistry more over the long term than a GBA SP (with only a small screen and no disc drives) draining its battery to an equivalent percentage.

 

[fart]

if i were to hazard a guess, if current draw makes a difference, it's due to heat. bigger batteries (ie, for high current devices) also have more complicated management systems

from your link:

In many respects, Li-ion provides a superior service to other chemistries, but its performance is limited to a defined lifespan. The Li-ion battery has a time clock that starts ticking as soon as the battery leaves the factory. The electrolyte slowly ‘eats up’ the positive plate and the electrolyte decays. This chemical change causes the internal resistance to increase. In time, the cell resistance raises to a point where the battery can no longer deliver the energy, although it may still be retained in the battery. Equipment requiring high current bursts is affected most by the increase of internal resistance.

Battery wear-down on lithium-based batteries is caused by two activities: actual usage or cycling, and aging. The wear-down effects by usage and aging apply to all batteries but this is more pronounced on lithium-based systems.

The Li-ion batteries prefer a shallow discharge. Partial discharges produce less wear than a full discharge and the capacity loss per cycle is reduced. A periodic full discharge is not required because the lithium-based battery has no memory. A full cycle constitutes a discharge to 3V/cell. When specifying the number of cycles a lithium-based battery can endure, manufacturers commonly use an 80 percent depth of discharge. This method resembles a reasonably accurate field simulation. It also achieves a higher cycle count than doing full discharges.

cool. thread over.