Quote:
Originally Posted by TonyS9
Gassing is the bit you need to avoid. Anything above 12.9V (2.15V per cell) is fine according to my research. 14.4V just happens to be the max stated for most batteries to avoid gassing. 12.9 to 13.3V isn't worth arguing about. A 940 charging at 13.3V would be slow charging and considered faulty at 13.3V.
The datasheets for Bosch S4 and S5 both state for standard charging (meaning continuous) that 14.4V is the "maximum". Sadly most battery datasheets are rather limited, it seems this information is privelaged, but I can say for certain that either Bosch batteries have reduced their charging range or they are perfectly compatible with old volvos despite them using Calcium.
https://www.ez-catalog.nl/Asset/3c4b...-S5-007-EN.pdf
My experience also says they work just fine, if you have a reasonably well working charging system, even over short journeys.
The reason I provided the halfwit link was to show a potential explanation for this "belief". Its more common now for old cars to have calcium batteries and faulty/poorly performing charging systems. Due to this type of misinformation rip-off mechanics will simply sell you a new battery, blame the calcium until you come back a year later with the same problem with a different battery that has calcium but doesn't state it.
There are also a number of different kinds, Yusas talk about Silver Calcium and Calcium/Calcium. It looks to me like all batteries now are Calcium instead of Antimony due to the reduced temperature aging characteristics, and increased voltage tolerance. The lastest types being AGM and EFB for start stop use, and you will want to drive those as hard as possible for recharging.
While it is hard to prove one way or another, I do think if there was a difference it would have to be stated in the datasheet. That is where the court will draw the line in a claim. |
That data sheet is March 2008 Tony, i wonder if Bosch have updated it to reflect the correct charging voltage? To clarify, when i said it needed to be gassing, i should have said "just short of gassing", you don't want excessive gassing, that's certainly agreed!
The trouble is, most mechanics and most independent car accessory/spares shops don't actually know the correct charging voltage for calcium batteries. I had this argument with the owner of my local car accessories/spares shop and explained it to him and he wouldn't have it, kept insisting the customers alternator was faulty. I suggested a "normal" lead-acid battery with lead-antimony in stead and the next time i went in, the owner made a bee-line for me and thanked me for helping and apologised for not believing me. He had apparently got his battery rep to check and what i'd told him was confirmed after the rep found out as he didn't know at first.
For the record, i have diagnosed many charging faults, stripped and reconditioned (not rebuilt, there's a big difference!) many alternators, starter motors and other things. When i say "many" i don't mean 50 or 100 but thousands that i never kept count of. During the various processes of testing and reconditioning, each alternator was tested on a test bench, purpose built for the job to maximum output and if the alternator on test didn't achieve 14V at maximum output, it wasn't working correctly. Please note this was before "smart" alternators that detect by some witchcraft i haven't looked into whether they have a "normal" or calcium battery and adjust the output voltage accordingly.
As for buying an "adjustable" voltage regulator for that Bosch alternator in that video, there is a more cost effective solution which is to cut the earth tag off the regulator and replace it with a 10A rectifier diode, forming a loop on the end to replace the ring on the end of the earth tag. It's fiddly to do but saves a few £££ but needs no separate setting up.
I did similar on my Rover alternator but as that is battery sensed and not machine sensed, i could do it by cutting the battery sense wire, fitting a 2-pin Supaseal socket and using two plugs, one with a simple wire link and the other with a 10A rectifier diode in it. With this arrangement i can switch between 14.4-14.0V (standard output) and 15.1-14.7V (boosted voltage for calcium battery) but as i currently have a calcium battery on the ROver, i'm obviously running with the boost diode in.
If/when i need to do the same to the Volvo, that's the method i'll use.
