Best Charging Practices

[crisscross5]

What is the best way to maintain the battery on my Redfly? Keep it plugged in and charging when not in use? Let it run down? Just curious...

 

[itsy]

Good question, I am curious to know this as well since there is a lot of conflicting information out there on charging practices

 

[wodin]

What is the best way to maintain the battery on my Redfly? Keep it plugged in and charging when not in use? Let it run down? Just curious...

I've killed more than one LiIon battery by leaving it plugged in for extended periods. I don't know if the REDFLY is different, but I'd be surprised if it is.

 

[laurieny]

Our advice to make your battery last as long as possible is to avoid as many deep cycle charges as possible. A deep cycle charge is where you let the battery completely drain down to virtually nothing and then recharge it back to full. That is the process that produces the most wear and tear if you will. If leaving it plugged into the power adapter is a feasible option in your use of the REDFLY, this is fine and it has minimal impact on the life of the battery. We have units that are always plugged in on our test racks and have been for more than a year already.

Thanks,
Laurie

Director of Engineering
Celio Corp | REDFLY

 

[graham.hughes]

We have units that are always plugged in on our test racks and have been for more than a year already.

If they're always plugged in... how do you know what the battery life is like now??

Graham.

 

[wodin]

I have two Sony laptops that I left plugged in and running for several months. Both of them now have non-functional batteries. Won't take ANY charge, and on one of them I have to actually take the battery out or it won't even run on the power brick. It just says I have a dead battery and refuses to boot. This happened to both of them well before the year or so life expectancy of a liIon battery.

 

[graham.hughes]

It's almost impossible to get any LiIon advice that is anything more than folk-lore.

Common advice:

* Prefer "top-up" charging over "deep-charging".
* Deep-charge once every 20-30 cycles.
* There is no harm in leaving the charger connected when at 100% (it will disconnect itself to prevent damage).
* You can damage the battery by fully discharging it (however, it should disconnect itself to prevent damage).

This conflicts with the experience of many of us, including me. I have many mobile phones, all of which I discharge to the point of a battery warning, then fully charge. They have long life-times. My IBM ThinkPad, on the other hand, which I frequently topped-up, has a completely dead battery (holds zero charge), and has done since about a year after I got it.

Nokia's advice covers nothing about charging regime, simply:

Extended or continuous charging may shorten the battery lifetime. Do not leave a fully charged battery connected to a charger, but always unplug the charger from the electrical plug and the device when not in use. To avoid continuous charging, do not leave your device for charging over night.

Sony Ericsson's advice is just:

New or idle batteries can have short-term reduced capacity. Fully charge the battery before initial use.

Lots of people claim that a LiIon battery needs several charging cycles from new before reaching its maximum capacity. I have experienced this, but it could just as easily be because I play with a new gadget a lot when I first get it. It's not surprising that I initially experience a short battery life.

Interestingly, I found an interview with the Sony VAIO-G developers:

Futoshi Kawata (Software Design Project Leader): The Battery Care Function helps conserve battery life to assure extended use. Normally, a battery is recharged 100%. However, this function extends battery life by resetting full recharge capacity between 50% (super-caring recharge mode) and 80% (caring recharge mode). It is well known that repeated "additional recharge" of nickel-cadmium or nickel hydride batteries affects the battery (lazy battery effect) to gradually reduce the battery recharge capacity and ultimately shorten battery life. However, the lithium-iron batteries of the VAIO G have different properties. Additional battery recharging does not have the same effect on the memory of this type of battery but it is still beneficial to keep battery recharge capacity at less than 100%. While overall benefits depend on how the VAIO G is used, research shows that there is virtually no decrease in capacity when recharge capacity is controlled at 50%.

If I understand this correctly, they actually deliberately prevent the battery from being fully recharged, in the belief that a 100% charge shortens the battery life. The ideal is to charge only to 50%. This doesn't mention how much you should allow it to discharge, but presumable you would need to drain it quite low, or have only about 30 minutes of battery life!

Confused? Me too...

Graham.

 

[mknollman]

wow - I am going to just stick with using it down to 1/4 and then charging to full. I will say that from my tech nerd experience - li ion batteries when left on the charger almost constantly most definitely suffer from it. Other than that - I think a lot of this is voodoo.

 

[graham.hughes]

I think a lot of this is voodoo.

I think so too.

I looked for advice from Nokia and Sony, figuring that they've made hundreds of millions of LiIon powered devices, so if anyone knows, they should. But, they don't really seem to have any advice at all.

Until some reliable (by which, I mean substantiated by research) information appears, I'm sticking to these rules:

1. When it says "battery low", I plug it in.

2. When it says "battery full", I unplug it.

3. If I occasionally use it past the "battery low" warning, or I recharge it when it's still half full, I don't worry about it.

Graham.

 

[wodin]

Oh yeah, and if your going to leave your device always one and plugged in, take the battery out if your can. I know, on the 'FLY, iPod, iPhone and many other devices it don't come out! (ever wonder why that is?)