K-7 replacement battery D-LI90

The comment on voltage is correct but misleading this is from Wikipedia.

Voltages of greater than 50 V applied across dry unbroken human skin are capable of producing heart fibrillation if they produce electric currents in body tissues which happen to pass through the chest area.[citation needed] The electrocution danger is mostly determined by the low electrical conductivity of dry human skin. If skin is wet, or if there are wounds, or if the voltage is applied to electrodes which penetrate the skin, then even voltage sources below 40 V can be lethal if contacted.

I've asked this before but forget it

Does anybody know what size of Li-Ion cells there are in the battery pack?
I wonder if you can make a high capacity one for less money.

The same size as the capacity of the battery. I guess there are two. Each of 3.7V ( a lion standard I think 3.6/3.7) so each cell will have the same capacity 1860mAh.

I think the China batteries are already as cheap as they go. They just use "higher quality" stuff (or quality control) for the real ones. So expensive for guaranteed quality and cheap for reasonable likelihood of not busting into flame.

A member here once opened up one and made photos of what's inside, it was indeed two normal Li-on cells like AA but the problem is there are several different sizes

If these will fit that would be great, you would have a 2600 mAh than link

The place to go for things Li-ion based is over to the nutters at CPF.

Yup, that was me, and I did it to prove a point in an older battery discussion.

The 7dayshop ones at £5.99 will be fine, might as well get 3 of em while you're there, you never know when you will need em!!

http://www.dealextreme.com/details.dx/sku.2640


http://www.qualitychinagoods.com/ultrafire-18500-1600mah-protected-batteryuf1850...

I always find reading the CPF thread about exploding li-ion cells puts me off experimenting. I've melted enough things with shorted NiMh. Also the thought of putting something home made in the K-7 worries me.

Thank you Danny, those are 18500 batteries too bad the longer 18650 won't fit

The K7 batteries are larger than the K10D/K20D ones anyway, but as with anything else you get what you pay for. OEM batteries may not be cheap, but they're up to spec and as reliable as it gets.

A friend of mine gave me his GX20 to sell, with an assortment of batteries. The Samsung and Pentax batteries were fine, not a mark on them, but the cheap ones were coming apart and the labels had worn away to nothing as well.

I just think if a company thinks cheap in one area, it thinks cheap all round.

John how much longer are they?
If they are around 70mm than they use the 18650 batteries so you can up the capacity quite a lot

I just measured the battery compartment of the K10D and that's 60mm deep so you can't fit 65mm inside that

edit: looked up the size of the K7 battery and it's 55mm so those are 18500 as well

Out of interest, for my K20D/K10D I have 4 regular batteries and 3 'cheap chinese' batteries. never noticed any difference between them.

Some other data.

link


link

Regards

Wrong batteries those are 18650 and those are 15mm longer than the 18500 that are in the Pentax so they won't fit

The best I could find were the TrustFire 18500 1800mAh
The cheapest I could find was here link
£8,63 for 2 (Free P&P)

I don't understand this discussion. Here you are spending hundreds of pounds on a camera, then trying to save a few pounds on batteries. Doesn't make sense to me.

Surely the time spent and the risk involved are not worth it.

If you can afford the camera, you can also afford decent batteries.

I think that spending £50+ on something so simple as a battery just rankles, Terry.