The lithium ion batteries in PowerBooks

Discussion in 'Mac Help/Tips' started by Shadowplay, Dec 20, 2002.

  1. Shadowplay macrumors newbie

    Dec 20, 2002
    I own a Pismo PowerBook that I've had for over a couple of years now. As I understand it, the lithium ion battery degrades in capacity over time... so between having a 2-year-old-plus battery in my PowerBook coupled with the fact that Jaguar has crappy power management, I'm lucky if I get a full hour out of this thing before it dies. Never a good thing if you're trying to be a road warrior.

    Obviously, I'm going to buy a new Pismo battery. But I'm trying to figure out how to prolong the life of it, so I've been doing some research and all I get are confusing answers. So maybe you can help.

    1. With a new lithium ion battery, I've read that the first thing you need to do is to fully charge it, then fully discharge it, and then fully charge it again before you actually use it. But that seems to conflict with other reports I've seen that state that fully draining a lithium ion battery actually damages its capacity. And one site says that you should fully charge then drain your battery three times when you first get it. Which is correct?

    2. Is it safe to keep your PowerBook plugged in indefinately to an electrical outlet? I used to do this with mine for weeks on end, because I didn't need to move it around. But does that kill your battery's capacity over time? Or do you need to "excercise" it regularly by draining it then charging it?

    3. Reportedly, the lithium ion batteries in the Pismo are immune to the "memory effect" of older type batteries. (That is, if you drain a battery 50-percent, then charge it, and do this day after day, the battery eventually "forgets" the 50-percent it never uses.) But then some folks recommend that you drain a lithium ion battery to different levels before recharging, just to be on the safe side. So are Pismo batteries immune or not to the memory effect?

    4. Do you just have to bite the bullet and buy a new battery every 18 months? Are there still going to be new Pismo batteries available in 2 years?

    Any help is appreciated. Danke.
  2. yamadataro macrumors 6502

    I'm under the impression that draining/recharging start up process is for activating the chemicals fully, although I'm not sure how much effect it has on the life time. Li-ion is memory effect-free.

    FYI: Sony's Li-ion for camcorders lasts for 500 recharges (as they say). So Apple's are about the same life time, I think.

    I once wondered about the future availability of my older PowerBook models. But I've realized that I'd be using another PowerBook by the time I start to have difficluty finding old model batteries.

    I know fresh ones for Duos and even the PB2400s are still around. These are either under original Apple brand or 3rd party brand. Popular PB G3 will probably enjoy a long lasting battery distribution because of the large number of G3s sold worldwide. I'm estimating another 10 years at least, considering Duo's is more than 10 years old now. And obviously Apple doesn't make batteries on their own. I know at least one model were Fuji made in Japan. Some maniac Mac shop in Tokyo even offers chemical component replacements for your very old models. They reuse the plastic casing and replace the content!!!
  3. yamadataro macrumors 6502

    An addition to my post above:

    - You can never completely discharge your PowerBook batteries because the PowerBook dies long before the battery's zero charge level as long as you discharge them on your PowerBook. Even at the sleep mode, PowerBook requires considerable amount of power. To completely discharge a battery you need a dedicated discharger (with an electric heater-like structure). The battery manufactures are just recommending battery condtioning for 3 first uses on "consumer-level devices", I believe.
  4. alex_ant macrumors 68020


    Feb 5, 2002
    All up in your bidness
    Inside the TiBook box when I got mine last year was an insert that recommended completely draining the battery once right away and then completely recharging it. (Or was it the other way around? Oh well, probably doesn't matter.)

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