Replace Your VCII or VCII+ Backup Battery

Link to Alan's VCII replacement battery tips

Note: This information is only provided as is and, this site or anyone affilated with it is not responsible for damage to any VCII or VCII+ board that might be caused by this information. Use this information at your own risk, for testing purposes only.

Why do you want to do this?

If your VCII or VCII+ is about 10 or more years old you might consider replacing the backup battery, as it holds the VCII(+)'s unit ID numbers and if this informaion is lost your unit will become useless. Second reason is if the battery casing leaks out any battery acid not only will your VCII(+) become dead, your receiver could also become usless. As battery acid is toxic and will eat through your receivers motherboad, and could even leak onto other equipment in your audio/video rack.

Can I test my battery life?

Their isn't any real way to know if your old battery is good or not as with the type of battery used, it could read proper voltage today then tomorrow become dead.

How long will my new battery last?

If you replace your backup battery it will last you for the next 10+ years.

Note: As more and more program providers adopt digital (DCII) programming, the use of your VCII(+) will become less. How long will VCII(+) programming last before its all gone to digital no one knows.

Before you start it should be noted, removing backup voltage from the module will render it useless, & this is not reversible.


You want to connect a 3 volt battery in parallel with the existing battery, so when you remove the old one the board doesnt lose the battery backup power. If you lose voltage durring any part of the operation, your board will become useless. Option two is to hook up a temp. battery and solder out the old battery then put in a new battery.

It can be described as jumpstarting a car, you just want to hook + to + & - to-
BEFORE you remove the old battery.

1) You need to buy a replacement battery.

VC2 (010.018,019,032) Tadiran TL5101P 3.6v 1/2AA .95Ah Axial Lead Cell.
Mouser P/N 667-TL5101P $5.25 USD ea

VC2+ Tadiran TL5955TP 3.6v 2/3AA 1.65Ah Polarized Solder Tab Cell.
Mouser P/N 667-TL5955TP $8.21 USD ea
(axial version P/N 667-TL5955P)

You can order these batteries at Mouser, which does not have a minimum order ( or you can purchase them at radio shack.

For Radio Shack go to Radio Shack on-line. You want a Tadiran 2150P Axial Pin 3.2 volt lithium battery. Put 960-0004 in the top search box or try clicking here, the cost is $7.99 ea + S&H plus tax. (Part is: TL2150P 3.6V/850mAh 1/2 "AA" Lithium Battery)

Note: You may actually want an axial lead cell to replace the solder tab types if you do not intend to fully remove the old cell completly from the PCB. You can pretty much use any Sub AA cell as long as it's 3.6v around 1-1.6Ah.

Remember, removing backup voltage from the module will render it useless.

2) Open your:


Option 1) This can be dangerous: Solder the Tadiran battery in parallel next to the existing battery using the same solder terminals that the old battery is attached to. Make sure that you match up the polarity (+ and - terminals) correctly. Make sure you don't disconnect the old battery as this will cause loss of power and your VC2(+) will become useless, until the new batteryis fully connected. If your batteries are of different voltages the old battery could heat up and explode.Go to step 4 a.

Option 2) Locate CR12 on your board then put an aligator clip (RED) to the cathode "banded" side of the diode CR12. This will be the positve lead of your temp. battery. Make sure you install your temporary 3.6 volt battery, + side to CR12 and – to ground pad, which is on the corner of the VCII board as a big square like silver color pad. Note if you use a different type of battery not the exact same as your board orginally has it is a good idea to install a diode. This is to isolate the two batteries connect an "IN914" diode in line with its lead, making the cathode "banded" side towards the board CR12.Go to step 4 b.


a)Finally remove the original (old) battery after you've soldered in the Tadiran battery. You can easily do this by cutting out the old battery with a pair of wire cutters. It's not advisable to leave the old battery in since it will drain power from the new Tadiran battery as the old battery loses its charge. If you cut the old battery it could blow up and damage you and your equipment, take high caution and wear saftey protection.

b) Now it is time to remove the original battery and you might want to use solder sucker to remove any of the old unwanted solder. Then solder in the new 3.6 battery as it was insatlled before + to the positve side and - to the negative side. Don't install the battery backwards!! Finally remove the temp. battery you installed before and your done.

Note: Some people who have tried this battery replacement have had their old battery leak out a toxic substance, when removing the old battery. Please be very careful and wear glove and/or eye protection.

Note: Follow Alan's link for pictures of this operation.