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

[Kiriakos GR]

ROUND 1 .....
Not fake lithium 18650 they sold no less than 6~8 Euro its one.

The Bosch thermal sensor it will stop the charge at 50~55C , basically this stops from charging a battery pack this left under the hot sun in the summer.
Your BMS does not look like this having it own temperature sensor, and it should have one, because this is now their protector.

One of less important issues that you will face by using original charger, this is that at charging cut off,  the charger will still deliver pulse voltage that the energy will be very low so to be used from the BMS balancing circuit (if there is one at charging mode).
Most cheap BMS they are capable at balancing due discharge.
You may add too small female banana plugs at the Bosch charger as I did too, by this way you will be able to monitor the charging voltage.

ROUND 2 ....
 
If you think going 100% Lithium?
I can pass one second advice only if your Bosch charger this using a real AC/AC transformer, does it?

[Gianluca]

My charger has this tab you see and my charger has this card you see and it is original Bosch similar to this in the photo that is not original ... I begin to think that I need to change my charger for this type of batteries ....

[Kiriakos GR]

I need a picture of your very own charger internals.

[Gianluca]

Here is what is required 

[Kiriakos GR]

I have good news and bad news. 

The good news ... this has a real transformer.
The bad news ... PCB this holding the metal contacts in place.

The next idea this is removing this PCB and use instead a DC/DC back converter with adjustable current (Three pots ).
Have a look here so to get some ideas. 
https://www.ittsb.eu/forum/index.php?topic=1524.0

[Gianluca]

Thanks for the info

[Kiriakos GR]

Thanks for the info

You are welcome 

[Gianluca]

Good evening, I apologize these may be fine for batteries?

https://www.ebay.it/itm/LOT-DE-20-RESISTANCES-RS64Y-1-4W-0-25W-1k69-Ohms-1k69-1/181465367245?hash=item2a402dc2cd:g:9lQAAOSwMzVTw8JU

Thanks 

[Kiriakos GR]

Yes they are what you need,  but try to negotiate the price by getting five of them. 
This seller is very expensive.
True retail value for such resistors this is  0.10 € its one at local electronics shops. 

This Italian seller has more reasonable prices and I did order from him too, just  send a message if he has what you need.
https://www.ebay.co.uk/usr/computechfg?_trksid=p2047675.l2559

[Gianluca]

Hello,
thanks for the valuable suggestion ..
An ignorant question that I am but with so much curiosity ...
Waiting to be able to change my charger, I tried to charge the battery without this resistance and I saw that the battery is still recharged  ...
Now mine was just a small test (done unconsciously) .. I don't understand the usefulness of this resistance if it is connected only to the negative pole of the battery and to the Key tag
Thanks

[Gianluca]

Yes they are what you need,  but try to negotiate the price by getting five of them. 
This seller is very expensive.
True retail value for such resistors this is  0.10 € its one at local electronics shops. 

This Italian seller has more reasonable prices and I did order from him too, just  send a message if he has what you need.
https://www.ebay.co.uk/usr/computechfg?_trksid=p2047675.l2559

have I found these even if smaller ones can be fine anyway?
https://www.ebay.it/itm/25-RESISTENZE-1-69-Kohm-1-8-watt-1-strato-met-25-pezzi/230493224642
Thanks

[Kiriakos GR]

I don't understand the usefulness of this resistance if it is connected only to the negative pole of the battery and to the Key tag
Thanks

BOSCH was having a wide range of chargers, slow charge speed, medium charge speed and FAST charge in just 30 minutes.
I do not know which specific model of charger this requiring such a additional confirmation due the Key tag (resistance value) so to start charging, I can only speculate that Fast Charger model this will require it at 100%.

Because non Genuine BOSCH battery this will explode under 30Min Fast charge.   
BOSCH  genuine battery packs was using Panasonic NiCD them able to be charged with 1.7V per cell.
Chinese NiCD they follow 1.5V max charging guideline, these at 1.7V they will run hot or even explode.