E30 Zone

I'm looking to sort out my SI Board when it comes to replacing the lithium cells so I can get the service indicator back to normal. Soldering the new cells in are proving a problem as solder doesn't stick to the battery terminals. So to solve the problem I'm looking to use a battery holder to hold the cells and then solder that to the contacts.

Question is at this point is - Are the cells/batteries on the SI board connected in serial or parallel?

Hope the question makes sense and appreciate any help! Ta

have you tried sanding the terminals to make the solder stick better.

VDO SI board batteries are connected in series.

I've never yet found a lithium battery that needs replacing, but if you are sure they do, what's wrong with using cells with tags on? The cell won't like direct soldering onto its ends.

Did try filing the terminals on the new cells to create a bit of key for the solder but made no difference. I admit that I should have checked the voltage on the old cells but I was trying to sort it out before heading off me holidays so was a little too hasty. I also should have used cells with the tags already on but once again I was cutting corners! Lesson learnt me thinks...

Just had a call from a mate and it turns out a mate has got a spare SI board so I'm gonna chuck it in mine. Cheers for the help gents.

Note that lithium batteries and niCd batteries are fitted to different designs of board. Lithium batteries cannot be used on boards designed for NiCds, and vice versa.

This is another topic worthy of a article I think!