[wibbly]

oh i totally understand the specifics of battery charging, i was just surprised that several hours wouldn't charge a battery from half charge to full.

i wouldn't consider that typical for batteries at all. perhaps pentax is smart enough to use less aggressive chargers to increase battery life.


Thanks for the input.

[crewl1]

the world's stupidest thread, battery charger

This is in no way the world's stupidest thread. There are far more stupid threads elsewhere, and not on this forum either.
I would say that the title of this thread is not the smartest, though.

[wibbly]

I use a lot of forums and I'd be upset if someone posted something this dumb on one of them. Just trying to avoid being a huge hypocrite

[ScooterMaxi Jim]

Wibbly,

I didn't intend to imply you didn't know the charging specifics, but as you have noticed Pentax takes an especially slow-charge approach. The first charge on all my various Pentax batteries have taken a very long time. I'm sure that this is related to the proper forming of the battery. After a few charges, the battery tends not to take so long to recharge for whatever reason. My sense is that the battery when it arrives is far less than half charged - even if the camera indicates otherwise. If it was me - no matter how tempting - I wouldn't power up the new camera with anything other than a fully charged battery. (Luckily, in the case of the K-3 arriving I already had the right spare battery in my arsenal as the K-01 - and several others - use the same battery.)

My refresher was simply intended to sum up best practices for the benefit of anyone who might come across the thread without knowing much about these things.

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Last edited by ScooterMaxi Jim; 12-12-2014 at 09:13 PM.

[emalvick]

I don't know a ton about batteries, but many rechargeable batteries need to charge from an empty state. Charging from a half-full state doesn't really charge things any faster.

The other thing is that battery charging is not linear. Batteries will charge to something like 90% fairly quickly, but the last 10% can take almost as long as the first 90% does.

I know there are electronics people here that can probably give better information.

Finally, these Pentax cameras generally show that "half-charged" symbol when they have about 20% left in them (give or take). That symbol to me is more of a warning that you'll need a fresh battery soon. When you get to the zero level, you have about 10 shots left, although I've been surprised to get a lot more and even a lot fewer on certain occasions.

[link81]

That's kind of the nature of lithium batteries. they hold a relatively flat discharge curve, but when they're dead, they die fast. Other chemistries have a much more gradual curve. (linear curve? that sounds odd) They tend to die a slower death.

[emalvick]

That's kind of the nature of lithium batteries. they hold a relatively flat discharge curve, but when they're dead, they die fast. Other chemistries have a much more gradual curve. (linear curve? that sounds odd) They tend to die a slower death.

Yeah, that's kind of what I was getting at. Charging is kind of the same way. It's more noticeable with cell phones for instance because they tend to report their charge levels. I'm always surprised at how quick my phone will charge to 90 even 95% and how long that extra 5% can take.

That's actually not a bad thing, and I believe that is how quick chargers work. They don't charge the battery fully opting to stop at that 90 to 95% range which could be nearly twice as fast as a full charge. Of course other things such as current, voltage, and battery size will have an effect.