Rollei E36RE Excell Battery 12V Rebuild

[ic-racer]

My Excell battery for the Rollei flash finally gave out. This battery is no longer availabe, (though two 5v Hasselblad batteries can be stacked together at a premium price).

I took the battery apart and it has 10 AAA cells. This should be a simple re-build.

PS: The original Varta battery used ten V500RH button cells stacked together.
V500RH

 

[Grif]

thanks for the tip!!! (never thought about AAA's) I've hacked up a belt pack for mine using C cells,,, dry cells last forever.

 

[ic-racer]

Ok, so I was able to get 10 batteries from Zbattery for less than 10 bucks. I soldered the batteries together in the same configuration. Everything went back together just fine and it works great. The key elements are the appropriate diameter and length cardboard tube and the tight-fitting metal caps for each end. I should be able to re-build the battery over and over again.

PowerIzer AAA 1000mAh NiMH Rechargeable Batteries, 10/pack $8.95

 

[Grif]

Any chance they were solder tabs? Or did you solder direct to the end of the cell?

 

[Ron G]

I found a place in Colorado that will build these packs very reasonably if anyone is interested.
I had to replace the cells in an old Mecablitz flash that I bought in Germany in the early '60s and they did a great job for me.
THe flash originally had four of those round cells in it.Ron G

 

[Nicholas Lindan]

Digikey will also make up custom battery packs with welded tabs.

http://dkc3.digikey.com/PDF/US2010/P2461.pdf

They also sell tabbed batteries and extended capacity industrial cells.

 

[ic-racer]

These did not have tabs. I soldered them with little bars just like I would solder together pacs for rc cars and planes etc. To get them in the appropriate pentagon I hot-glued 2 at a time together, then those 4 were fit around a 1/4" dowel. Then the last one was glued to the other 4 after removing the dowel, squeezing the 4 together slightly to make a perfect pentagon.

I also just rebuilt a little Excel PX30. Basically it is a little cardboard tube with a modern 3v lithium battery at one end. I just took it apart an replaced the 3v lithium battery then taped it back together.

 

[ic-racer]

UPDATE: The batteries I got from ZBATTERY did not last very long. So I am going to re-do this again with some Sanyo AAA Nicads. It will be $35 for the ten batteries and I ordered them today. I should have used the Sanyos in the first place.

 

[ic-racer]

UPDATE:
I got a new set of Sanyo AAA and put them in the cardboard shell from the original Excell battery. They work great.

I then noticed that the inexpensive NiMH batteries still had some voltage on them and I there was a cold solder joint on one of them. Could these batteries be salvaged?

I noticed that two 35mm plastic film canister holders are the exact correct dimensions of the original battery. The two groups of 5 radially oriented batteries fit perfectly in the film canister. I just cut a slit on each end and had the metal strip come out each end and put some insulation between the two 5-battery assemblies and then taped the two canisters together so the closed ends were on the top and bottom. I put red tape on the POSITIVE terminal end. It turns out that after some coaxing with repeated charge-discharge cycles I was able to recover the NiMH cells and get them to hold a full charge again. That is good because they were less than a year old. I'll just have to remember to never leave the flash in the 'on' position to avoid the complete battery drain that inadvertently happened.
I actually have two E35RE flashes, so now I have a good working battery for each one.

 

[Nicholas Lindan]

Soldering to the ends of batteries is, in general, a bad idea: the contacts are usually nickle plated which can't be soldered reliably with standard electronic solder; the thermal mass of the battery makes it hard to get the contacts hot enough for a reliable joint; the heat can damage the battery internals. Soldering to a lithium battery is a very bad idea.

Tabbed batteries have thin solderable metal strips spot welded to the battery contacts and are meant for making battery packs. There is usually a small charge for the cost of welding the tabs. Most battery vendors - see above for Digikey - will make up battery assemblies by welding the strips between the battery terminals, often at no charge above the price of tabbed cells. I haven't had Digikey make up a geometrically complex pack - like a pentagon - but emailing them a sketch or photograph might get results.

I've had very good luck with Panasonic's heavy duty NiCads and NiMHs.

 

[ic-racer]

All the cars at the Radio Control nationals (held in Independence, OH every year) and just about every other race use soldered battery packs. Thats how I learned how to make packs.
http://www.inlandcraft.com/howto/battery_pack/building_rc_battery_packs.htm

 

[Nicholas Lindan]

All the cars at the Radio Control nationals [have] soldered battery packs.

That doesn't make it the right way to connect batteries. From what I can gather with a Google search, the practice of soldering up battery packs is confined to the RC model racing fraternity. OTOH, soldering to battery terminals is proscribed by all battery manufacturers. I imagine people can make up their own minds on the matter.

On a serious note: soldering to a Li battery can cause a small explosion or fire with lots of chemical smoke, don't try it.

Tabbed batteries, designed for soldering, are easily available and are easy to use with no special technique needed. There is no reason for not doing a battery replacement in a reliable and safe manner.

 

[ic-racer]

In this case of a pentagonal orientation. The solder tabs don't line up from one battery to the next. In fact the Sanyo AAA batteries I used for the second pack DID have solder tabs but I took them all off. They were not in the correct orientation and they were pretty flimsy. I made new connectors out of thicker brass, since this is a high output battery pack.

Even if one did have a capacitive discharge battery welder, it is not a panacea. For example you will need to know how to set it. For example the $3000 PowerStream spot welder can be set from 0.1 Watt-second to 100 Watt-second with weld currents from 6400A to 80A.

Or you can make your own battery spot welder, like seen here. Looks real safe ....(check out 1:58 in the video)
http://www.youtube.com/watch?v=9spgDiU3_nw

 

[ic-racer]

Ok, so six years later the NiMh cells are dead. The next rebuild will involve this small 3-cell lipo battery that fits in the handle. Stay tuned....

 

[Black Rock City]

Ok, so six years later the NiMh cells are dead. The next rebuild will involve this small 3-cell lipo battery that fits in the handle. Stay tuned....

I'm thinking about doing the same thing. My only question is will the charging circuit need to be changed out in order to handle the Li-Po cell given that the charger was designed for Ni-Cad?

Also, battery chemistries differ from each other in how much current they can deliver. In addition, the discharge profile can differ. —e.g., during discharge, does the voltage stay relatively constant until the battery dies OR does the voltage drop as the battery discharges?

These semantic differences may not matter in this application but I thought it was worth mentioning. (Especially if there is a potential fire risk by applying a Ni-Cad charge circuit to a Li-Po battery.)

 

[ic-racer]

You should not charge the battery while it is in the flash handle. These LiPo batteries need 3-cell balance charger. I use an iCharger Duo 406.

 

[ic-racer]

Pictures to follow. I made a spacer with an electrode to contact the existing spring in the unit. There is a wire from the electrode contact that goes to one terminal of a JST connector. The positive side of the JST connector is soldered to the area where the end cap makes contact.
The LiPo battery is plugged into the JST connector and placed in the handle. The end cap keeps the battery in place but has no electrical connection (unlike the original battery).
The balance jack of the battery is not connected to anything. It is used only for charging out side of the flash.

 

[ic-racer]

Components for the project. Top is the old battery to gauge the size. Middle is the adapter under construciton. Wood is good because it is non-conductive. Below is a 850mAh 3cell (12.6v) LiPo.

 

[ic-racer]

 

[ic-racer]

The battery plugs into the adapter with the red connector. The battery is un-plugged from the adapter for charging. No over-discharge protection here, so be careful. However, if the battery gets trashed from over-discharge, a new one is only $8 USD

 

[paul ron]

The battery plugs into the adapter with the red connector. The battery is un-plugged from the adapter for charging. No over-discharge protection here, so be careful. However, if the battery gets trashed from over-discharge, a new one is only $8 USD View attachment 191457

Nice rebuild!

I made an external battery for my sunpak 611 years ago using a small 6V burglar alarm battery. I wanted a higher MaH rating than the original batteries so I can get longer life from a charge. I can trickle charge it using a charger I got from Wallmart for $6.

Gotta say, it also cycles much faster than the old NiMh battery pack in the head.

 

[ic-racer]

I see all the original photographs from this thread that had been hosted on PhotoBucket are gone. The original battery had ten AAA cells in two groups. It was a little neater because it all fit in a cardboard tube. The 850mAh battery in the pictures is too big to fit in the cardboard tube and just barely makes it into the 36RE handle. I ordered a 450mAh battery and it has the same rectangular dimension, but is thinner. It also won't fit in the cardbaord tube so I'll just go without the cosmetics and will be careful of the wires.

 

[ic-racer]

Just recharged the 450mAh battery. It holds the charge well.

 

[ic-racer]

Pictures from the first part of this thread are gone, so here is a re-post of the inside of the Excel replacement battery. You can see the ten AAA cells

 

[Fujicaman1957]

IC Racer-
Want my plans for an external battery pack for the E36RE? It uses a 12 volt gel cell.