BOSCH Ni-Cd 12V How should the battery terminals be connected?

[Gianluca]

Hello everyone, I have an old Bosch screwdriver from the 2000s. I found this battery in the house but it was disassembled and who knows where the pieces went. Now, assuming that it is impossible to buy (maybe I'm wrong?) only the piece of photo A, I have reconstructed the contacts (photo B).
I connected the contacts D and C together by inserting the temperature sensor but the charger does not charge. I am wrong, I remember when I disassembled the battery (10 years ago) that there was a small resistance inside ...
Thanks to those who can help me and thanks also to the administrator for accepting me in the forum.

[Kiriakos GR]

Hi,

Use alcohol all over the hot-glue (make it wet)  and carefully remove it by breaking it in pieces with small screwdriver.
Now extract entire connector and plates from the plastic body (battery housing).

This should look like as is in my picture.


 

[Gianluca]

Hello,
 thanks for your answer, however, I no longer have the original connector that you showed me in this photo ... Unfortunately it was lost, I rebuilt the contacts and glued with hot glue. My only problem is understanding how to connect this sensor. I see resistance ... What value does it have? Where should it be connected? Thanks 

[Kiriakos GR]

The resistance this is connected at minus and to key tag = Genuine Bosch battery.
The sensor get connected at minus and front battery tag.

The resistance this is precision type, use this link to verify the bands and accuracy.
You have to use identical in specifications resistance or else the charger will reject the battery. 

https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-resistor-color-code-5-band

[Kiriakos GR]

For personal use I have a modified battery box this converted to battery simulator ..  I can test any Bosch charger if this is working properly, and I can data log the charging process too.   

[Kiriakos GR]

5 bands resistors they are tricky, here is the color code info.
Resistor this is film metal.

[Gianluca]

For personal use I have a modified battery box this converted to battery simulator ..  I can test any Bosch charger if this is working properly, and I can data log the charging process too.

Good job

[Gianluca]

The resistance this is connected at minus and to key tag = Genuine Bosch battery.
The sensor get connected at minus and front battery tag.

 Did I interpret well?

Thanks

[Kiriakos GR]

Gianluca I will never hire you as my own assistant for an international project. 

Contacts :
Top = sensor
Polarity Plus
Polarity Minus
Key tag

We have run out of metallic contacts. 

[Gianluca]

I apologize but I am really a disaster to the limit you could hire me to put the equipment in order and clean.

Have I made progress now?

[Kiriakos GR]

Good job !  (finally) 

[Gianluca]

Thank you very much,
now I will find the resistance, make the connections as you suggest and try this new lithium battery pack.
As you can see from the photo, I made the connections wrong, the drill works but obviously does not charge the batteries ....
A perfect ignorant question ... I left this drill years ago because the battery packs were very expensive, now following a tutorial on youtube I found the pieces at low costs but the question is this. Are we sure that these lithium batteries are really good for my old charger which was then designed only for nicd batteries?
I don't want it to ruin my charger ... or to ignite the batteries. For example, it could happen that despite being charged, the charger continues to charge them because it does not recognize their state of charge?
Thanks