[aslyfox]

not sure if these questions have been asked and answered before, if so, I apologize

I have the Pentax K 3 and K 5 II with the optional grip/battery accessory. Currently the K 5 II is my back up camera and I am not using it. should I remove the batteries from it?

I have been using the K 3 with the original battery and a non Pentax replacement battery in the attached grip. I have been recharging the battery in the grip only. (I'm lazy and that can be done without detaching the grip from the body.) Should I rotate that battery with the one in the camera body so that both get drained and recharged?

at what level should I discharge the battery before recharging? Should it be completely drained or is it ok to recharge it even if there is still charge left in the battery.

Both grips allow the substitution of the rechargeable battery with AA batteries, should I use those some of the time or would it matter?

I use the grips even though I don't really need the back up battery because I like the feel of the camera with it.

thanks for all the advice and help.

[victormeldrew]

Lithium batteries are not fussy like the old Ni-Cad or NiMH batteries. Charge them whenever and at whatever level. If you are leaving them unused for a prolonged period they are best left part charged, not totally flat.
It is probably best to leave the battery in the unused body to prevent loss of settings and give it a charge periodically.

[photoptimist]

Totally draining a lithium ion battery (especially multi-cell batteries like those used in DSLRs) risks shortening the life of the battery. Some device makers do suggest occasionally using a LiIon battery until it's exhausted to help calibrate the battery-level indicator but I'd not do that too often (once a year) and only if you are really concerned about the accuracy of the battery level indicator.

Never leave a low/dead LiIon battery in the device -- the device will slowly continue to drain the battery until the battery is damaged.

As victormeldrew said, do leave a charged battery the camera to preserve the time/date settings of the camera and prolong the life of the tiny rechargeable battery built into the camera that keeps the clock ticking when you are swapping batteries.

For cameras that don't get much use, set an alarm on your computer to remind you to recharge or swap batteries in your backup camera very 4 to 6 months.

[UncleVanya]

My recommendation after researching this is that 40% charged is the optimal long term storage level for LIthium ION rechargeables for lifespan of the batteries.

BU-702: How to Store Batteries ? Battery University

[aslyfox]

You guys are great. Thanks for the quick responses

[fredralphfred]

Since the original poster mentioned it, I'd like to say, "Yes! You should use AA batteries periodically (NiMH) or more often because they're more standard and have less battery management issues than most Li-ION batteries." But realistically, most people get along with Li-Ion's just fine even though they cook them to death and then starve them to death repeatedly. My issue with them is mainly that I have to have a **** dedicated charger for each device that takes a specialty battery, but if people came to their senses and just used standard batteries, I could use one universal charger to cover everything (like flashes AND camera body).