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The Power Of Volts and Milliamps!!

Thanks for the replies. Are the two pieces that sort of look like resistors needed? I was thinking of making a custom charging stand similar to the original Rollei so I could simply drop in the battery pack and do a balanced charge. If I had those extra terminals it would make life easier to make it a drop-in charger.

Next task is sourcing batteries in Canada. I looked at the Hobby King link and an $11 battery incurs $30 shipping, and since they use UPS I know from past experience it's a $50-70 brokerage charge on top of that. Makes it much better to source locally.
 
As an update, I did a bunch of research into the LiPo batteries and decided it was too much hassle to use them. Instead, I went with NiMH batteries, as they were much less fussy about storage voltage and charging. They were already a significant capacity increase over the nicd originals, so I went with that. I contacted a battery place in Regina, SK who made them for me and spot welded the tabs on for $5. I though that was a good deal. The cell size is 2/3A for reference, not 2/3AA.

I bundled the 8 cell pack and wrapped it with 0.005" thick sheet styrene from the hobby store to provide electrical insulation and that just fit into the Rollei cans, but doesn't rattle.I did a short wire to solder to the endplate and the packs were done.

To charge them I found that 1" finishing nails are just the right diameter to make firm contact with the electrical contacts on the pack end, so I built a charging stand from cherry salvaged from a shipping pallet and put nails in teh end in the correct place such that the pack can only be inserted one way and pushes to the end and stop to engage the nail ends. Then I soldered a wire from an RC car NiMH battery charger to the nails and I have a custom Rollei charger for the pack with new batteries. So far my friend is reporting that the camera works just like new, and the batteries have excellent life.
 
Nice work! Yeah, Lithium Polymer batteries do have some downsides -- explosion/fire hazard being top of the list, and that goes double for custom-assembled battery packs and chargers that aren't matched to the pack. If the battery is built by someone with the right knowlege and skill, it's no more hazardous than that cell phone we all carry (which, yes, do blow up on rare occasions) -- but if it was built by Bubba, who has four different size tires on his truck and balances out the handling by hanging his head and left elbow out the window, even in the dead of winter, I'll pass, thanks just the same.
 
My latest battery project was to put Eneloop batteries in my SL3003 packs. Those have been great because now the SL3003 cameras are always ready to go without needing the 'quick charge' that I previously needed to do for the last 20 years.
 
I got a new lens for my 6008i so I used that opportunity to charge the battery. I undo the two screws and take the battery out so I can get to the balance connector and do a balance charge. Not too big of a deal, since I only need to do that once or twice a year.
 

If it was me, I might have gone that way, but I wanted it simple and easy for my friend, so now it's no different than charging the original batteries. He simply pushes the battery pack into the charging stand and plugs in the charger. No different than charging a phone.
 
I wish they make Eneloop batteries that would fit in the 6000 series battery pack like I put in the 3003 pack.



 
Thanks to the thread's author for the very useful information. I made a similar repack using an 850 mAh LiPo battery, but for some reason, the camera with the Schneider PQS 80/2.8 lens refuses to work with this setup. It says "charge the battery," even though the voltage is 11.5V. Meanwhile, the PQ lenses work without any issues at all. I've tested this on three different cameras and two different Schneider lenses; it's a mystery.
 
Yes I have a lens-body combo that gives the same error.
 
ic-racer said:
I'm working on an adapter plug so I can use an automated/computerized charger.
Click to expand...
NiMH requires a "delta-v" or specialized charger to detect when the battery is full to avoid damaging it. Does yours do that?
And do you monitor battery temperature, too, to prevent overheating during charging; I surmise that is what the thermistor is doing?
 
ic-racer said:
Yes I have a lens-body combo that gives the same error.
Click to expand...

I tested a setup with three lipo batteries, with a total capacity of 500mAh. The camera stopped displaying the "charge" and now shows almost a full charge. However, at certain shutter speeds, the mirror lowers and the body freezes. Only turning off and using the original battery helps in this situation.
Now I'm thinking of trying three 14500 battery's, 3.7v and 500mah each, maybe this will be a better solution for my combo
 
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ic-racer said:
Someone got it!
BTW I'm still basking in power...I have not had to charge for almost 2 months. Also, I discovered me 'broken' 33ft electric release works just fine now. A worn out battery won't provide trigger signal through the 33feet of cable.
Click to expand...

For the non-electricians here, could someone explain how to hook up batteries to increase the capacity? I know you have to hook them up in line to add the voltage and in parallel to add capacity, but how do you do that with 4 if you want the sum of their capacity without changing the voltage?
 

If you want the voltage of one battery but the capacity increase, hook all four in parallel. All negatives connected to each other, and all positives connected to each other.

For example, lets say you have four AA 1.5-volt batteries with 2,000 milliamp hours (mAh) each. Connecting in parallel would give you a battery bank with 1.5 volts at about 8,000 mAh.

Hooking the four batteries in series instead would give you a bank with 6 volts and 2,000 mAh. If you wanted the increased voltage of 6 volts and increased capacity, you would need additional battery banks, and the banks would be connected in parallel to increase capacity as well.
 
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