K-7 battery advice

Hello all

I've not had my k-7 long enough yet to drain the battery and I need a full charge tomorrow.

I also have a spare battery made by INOV8, which I just tested and the camera claims it's fully charged. Any experience with this third party battery? Can I rely on it for a half day solid shooting, and should it be pre charged?

My Pentax battery says it's half empty. I don't want to put it to charge now without it being drained first.

Any advice anyone please?

put them both on charge until the green LED goes off. THey will be fully charged and work for long hours allowing you to shoot all day (or almost) without depleting.

thanks nathan.

am i not risking reducing the capacity of the battery by charging before it's empty?

or can i effectively 'reset' the capacity by draining the battery fully next time?

thanks david that's extremely helpful. believe it or not this is my first ever camera with a lithium battery like this (only used AAs before).

roughly how long does a full charge take?

I usually plug it into the charger and leave it over night or all day - the light goes out when it's done, and there is no danger of "cooking" the battery!

It takes up to a few hours to charge the battery, depending on the state.

Although there's no memory effect, it's still a good idea not to charge unnecessarily as every charge shortens the life of the battery, whether it be from empty or half full.

Store your spare batteries in a cool place when possible as well.

Charge time is quoted in the manual...

Only partly true - with lithium ion batteries it is the total amount of charging done, not the number of times you charge the battery, that counts, thus if you charge from half discharged it only reduces the life by half as much as if you charge it from fully discharged (if you see what I mean) so you can regularly 'top up' your battery without detriment to its overall life. Also Lithium bateries hold their charge very well (unlike NiMH) so a fully charged battery stays that way (or pretty much)

Finally, if you are going to store a lithium ion battery for any length of time, they are best left about half charged (probably why they usually come that way when you buy them). They should not be stored 'empty'

I doubt it works like that in practice because I have noticed that with a 75%-full battery, for example, the charger takes more than 25% of the time than it takes to charge an empty battery. In other words, it takes disproportionately longer to charge a partly charged battery, for some practical reason.

I suspect that the charger overcooks the battery somewhat at the end of the charge, therefore you want to minimise the number of over-cooks by fully charging rather than topping up, when you can.

I have noticed with the Li-ion batteries I've used in various devices, it's the ones that I top-up rarely that last the longest.

Useful information. I have been scouring the web for a spare K7 battery and there are some that are not Pentax makes but are, I suppose, compatibles.
The prices of some of them seem extremely cheap compared with the Pentax battery - well under £20 - does anyone have any experience of these cheap compatibles?
Are they worth buying or will they discharge quickly or possibly not be good in cold weather?
Cheers
John

I swap between the Pentax and 3rd party battery continuously and I've never noticed any difference... works fine, fraction of the cost, no brainer

For Lithium Ion information.

link

Regards

I have just got an Inov8 from SRS for my K20. I haven't had it long enough to say that it is good or bad, but I reckoned that wouldn't sell a duffer.

I have an Inov8 battery in my K20D. As I have found with quite a few Li_ion batteries it does take a three or four discharge/charge cycles to give maximum usage and accurate reporting of the state.