The Power Of Volts and Milliamps!!

[ic-racer]

It has been quite a while since I rebuilt my Rollei 6000 series batteries. One was rebuilt around 2000 and the other around 2005 or so. As you may know the Sanyo Cadnica KR-600AE 2/3A batteries are no longer made, but there are replacements in that size with much higher milliamp rating. I went with these: http://www.batteryspace.com/nimh-re...00-mah-nimh-battery-1pc---rohs-compliant.aspx

 

[ic-racer]

Here is a battery that I last rebuilt quite a few years ago. It read 6V when I took the picture. I tried to restore it with some charge/discharge cycles on an automated charger without success. The pack with the yellow batteries measured 0V.

 

[ic-racer]

I put the new batteries in a box and used super glue to hold them together:

 

[ic-racer]

I made up solder tabs from brass sheet metal:

 

[ic-racer]

Solder the tabs in place:

 

[ic-racer]

Solder on the end plate:

 

[ic-racer]

Replace the padding and temp sensors:

 

[ic-racer]

Put it all together:

 

[ic-racer]

I just got back from shooting using the new battery. It really restored the camera to perfect function. The last few years, every time I picked up the camera the battery was dead. Charging only lasted for a day and even then the peak voltage was low.

I'm working on an adapter plug so I can use an automated/computerized charger. The pins need to be exactly 1.5mm. I'm searching for suitable materials.

 

[polyglot]

Hey, you know you can buy the cells with solder-tabs pre-installed (designed for making up packs!) instead of contact nubbins? That way you don't run the risk of thermal damage to the battery's chemistry when you solder the pack together.

 

[ic-racer]

I have always made my own tabs. I'm not sure pre-affixed tabs will line up correctly in a pack like this. Probably from habit, when I first rebuilt the pack in 1984, non-tabbed cells were all I could obtain.

 

[deisenlord]

I have always made my own tabs. I'm not sure pre-affixed tabs will line up correctly in a pack like this. Probably from habit, when I first rebuilt the pack in 1984, non-tabbed cells were all I could obtain.

The pre-built pack's work fine.

 

[deisenlord]

I also found one of the rare rollei power interface gizmos and its really great, I have a big NIMIH battery pack on a coil cord I plug into it. Go for days and days.

 

[gleaf]

Thin nickle strip bonded (pulse welded) for custom connections.

 

[ic-racer]

Here is my new charging setup:

 

[ic-racer]

This is the custom connector I constructed to link the charger to the batteries. That other wire is the thermistor probe, the battery just sits on top of it when charging or I use a rubber band to hold it close to the battery:
View attachment 71849
View attachment 71850



(double post? Some difficulty being encountered posting pictures lately; should be only two pictures posted)

 

[ic-racer]

Next is to make a charging adapter for the new SL3003 NiMH batteries.

 

[ic-racer]

Update: I'm traveling with the SLX and no charger. Day 5 and the battery is still going strong.

 

[andrewf]

I'm really impressed! Good work!

 

[FiatluX]

Just did mine as well, altho with presoldered cells..
Only to find that both my mags wont wind the film properly anymore, I´m guessing gummed up old lube or something similar after 12-15 years of no use. Sigh!

 

[E. von Hoegh]

"The Power Of Volts and Milliamps!!"

E x I = W
Where:
E= EMF in volts
I = Current in Amps
and
W = Power in Watts

 

[ic-racer]

"The Power Of Volts and Milliamps!!"

E x I = W
Where:
E= EMF in volts
I = Current in Amps
and
W = Power in Watts

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.

 

[ic-racer]

Update. The cells used in the battery finally gave out. They drain and charge, giving about 1000mAh, but they don't hold the charge very long. Just a few days.
Battery rebuild time again!

 

[ic-racer]

In this simplest form for testing, the connector allows the LiPo to be removed for charging on a LiPo balance charger. It is just a matter of removing the two screws holding the battery case together. There is also the option of doing a non-balanced 3-cell lipo charge with the battery in the case. The battery that I'm using did a non-balanced charge with 3mV cell separation. As good or better than some other batteries with balanced charging. Of course do this at one's own risk, after a few cycles one cell could get too low or too high. Non-balanced charging probably causes most of the lipo fires.

 

[ic-racer]

My measurements show the fully charged NiMh Rollei pack to be around 13V with my peak charger. My fully charged 3-cell LiPo pack is 12.1v with my lipo charger. The minimum cell voltage I'd like to avoid is 3.0, which would give a battery voltage of 9V, way below the 6008i cutoff. The 6008i also turns itself off after 40 seconds. There is the possibility of leaving the meter hold switch ON which may drain and trash the LiPo. However, a new LiPo is only about $10!

BTW: This is just an experimental pack. A more user-safe pack should incorporate this: