Pentax warning on rechargeable CRV3's

I started using rechargeable CRV3's in my istD. I loved them, and had two sets I always switched off on.

One day I tried to use regular CR-V3's instead and the battery indicator said empty. The camera would not work. I brought it to the shop in which I bought them and they tested another set which also would not work in the camera. They tested the battery charge which was fine.

I sent the camera in to Pentax. They sent it back in workable order with a notice not to use rechargeable CRV3's in it. I called to ask why and was told that the beginning charge is strong but falls off very sharply and can cause short circuits in any Pentax digital camera.

I don't know if I dare try them again, but I am not very happy as I was really enjoying them.

So just buy a bunch of rechargable AA's. Solve your problem with one simple change.

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42

I am doing the same. I bought a decent charger which charges each cell seperatly (most chargers charge in pairs).
This has increased the battery life even more.

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Camera:K20D|Ist*DS|Spotmatic II|MZ-10
Pentax Lenses: DA16-45|DA50-200|50A 1.7
Tamron Lenses: 28-200
Takumar Lenses: SMC 55 1.8
Sigma Lenses: EX DG 50-500 'Bigma'|EX 50mm Macro
Flashes: Metz 58 AF-1|Samsung SEF-36PZF|Pentax AF-220T

According to Pentax, the voltage in rechargeable CRV3s are higher than normal batteries.

I'm with 'arthur Dent' and 'Ava' on this one. The cheaper and better buy is rechargeable AAs

I have an *ist DL2 and the manual states that the use of CR-V3 rechargeables is to be avoided.

I use rechargeable AA's or non-rechargeable CR-3V's (after some cameras I've owned it's nice to have a choice)!

7 day shop sell a really neat charger (V800 or something) comes complete with mains adaptor with several different plugs, also a car adaptor, it charges 4 x AA or AAA all individually and for a really cheap price. The next best option to that seemed to be to spend a small fortune. Cycling my batteries through this charger a few times seems to have pretty much doubled their life. Mind you - i still carry a couple of sets of normal CRV3s as spares...

I cant see the point of CRV3's can anyone tell me why this battery was developed? ie; whats its advantage over AA's, its certainly not price! And if the CRV3 is that good then why did Pentax design the handgrip to take AA's? (or does it take CRV3 as well?)

As for the OP, I have only ever used the set of CRV3's that came with my camera, when they died I continued to use a set of Camlink re-chargeables I had for my compact, I then bought a set of Uniross 1300's then later bought a set of Uniross 2000's, none of these were particularly expensive or have supersonic chargeing times but they do the job.

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My Names Alan, and I'm a lensaholic.
My PPG link
My Flckr link

The problem I have had is that my camera never performed well with the other recommended rechargable batteries, but I am guessing from what I am reading is that the problem might be that I did not have a charger which charged individually.

I have had recent problems with some NiMH AA's, after using two of the four in a different camera for a day. The life of the four together seemed less, even after recharging several times, so now I've completely discharged them all (running them down with an electric toothbrush!) and am currently charging them back up again. I'll see how this goes, before splashing out on another charger.

Dan

You don't have to completely discharge them. Memory effect is nonesense with normal use. The only way one could get a real memory effect is by charging and discharging them exactly the same every time for hundreds of times and my exactly I mean EXACTLY. Every memory effect, if existing, is removed by the ^V charging method which most chargers use, they slightly overcharge every battery so if there is a memory effect, which is doubtfull it is removed by the charging cycle. What we think is a memory effect is mostly temperature induced drift and the capacity gets lower through normal use as well.

The problem is the charging cycle. Most chargers charge in pairs and if from that pair one cell appears to be 'full' the charger stops and so the other cell isn't charged completely.
When I charge my batteries with a good charger I NEVER see two cells which have the same capacity.

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Camera:K20D|Ist*DS|Spotmatic II|MZ-10
Pentax Lenses: DA16-45|DA50-200|50A 1.7
Tamron Lenses: 28-200
Takumar Lenses: SMC 55 1.8
Sigma Lenses: EX DG 50-500 'Bigma'|EX 50mm Macro
Flashes: Metz 58 AF-1|Samsung SEF-36PZF|Pentax AF-220T

I wasn't so concerned with memory effect, just the fact that 2 of the batteries had been discharged more than the other 2, and it seemed to be affecting their performance as a group of 4. I guess charging was stopping before all batteries were fully charged. By fully discharging all the batteries, I would be sure that they all started at the same point, so should have a more even charge between them.

I'll see how they get on now that I've done it.

Dan

Daniel,

Have a look at http://www.picstop.co.uk/Battery-Charger/Ansmann-Energy-8-High-Tech-Desktop-Charger (as recommended by MattM), you'll find that it'll charge the individual batteris rather than pairs or 4's (when most chargers stop as soon as 1 cell reaches full charge) Also test the cells too.

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Tim the Ammonyte
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K10D & sundry toys
http://www.ammonyte.com/photos.html

You shouldn't completely discharge any battery to the point where it reads 0V, or near to it. When fully discharged, a batteries internal resistance increases to a point where it might not recharge at all. To have all batteries (cell's actually) at the same level of charge before recharging is a good idea, but a 1.2/1.5 V Cell should not be discharged to much below 1.0V per cell. The best way to achieve this same level of charge is by using a charger that can also discharge to a safe point before recharging. I have a similar problem of recharging cell's in that I have only the type of charger that does one or two pairs at a time.

I'll be buying an Ansmann Energy 8 (takes up to 6 AA cells) to resolve this problem and rejuvenate my cells. The Energy 16 is a good option if you need to recharge 12 AA cells at atime IE: You have 4 in the camera, 4 in the battery grip, and 4 for a flash. Both Ansmann chargers will recharge the lot in about 4 hours. There is an Energy 4 model available too which does up to 4 AA cells at a time.

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Peter E Smith

My flickr Photostream

I got the following charger and it works perfectly as well. It allows you to set the charging and discharging current. So when I am not in a rush I use a lower charging current which is better for the batteries.

http://tinyurl.com/k3xb9

If the link doesn't work, try http://www.conrad.com
Article No.: 512266 - I5

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Camera:K20D|Ist*DS|Spotmatic II|MZ-10
Pentax Lenses: DA16-45|DA50-200|50A 1.7
Tamron Lenses: 28-200
Takumar Lenses: SMC 55 1.8
Sigma Lenses: EX DG 50-500 'Bigma'|EX 50mm Macro
Flashes: Metz 58 AF-1|Samsung SEF-36PZF|Pentax AF-220T

Neither of the two links works for me. I've ordered the Ansmann Energy 8 anyway. £40 form Picstop, £50 from Warehouse Express.

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Peter E Smith

My flickr Photostream