Elektrik: zwei Batterien im 750i - Fragen

[AnttiS]

Hi!

Did I get you right that it would be possible to charge the auxiliary battery via the "extra" pole in the engine compartment as shown in the picture above? Is this pole also under same type of cover as the jump start pole does....or do I need to have a tool to get access to it? Please advise.

Brgds

[Sinclair]

please simply look at the arrow in my photo/picture above,
you need a different mechanical access to this "+"contact

[Andrzej]

Yesterday i proved myself, how to charge both batteries via + and - poles in motor compartment. To check and make that properly i took batt. charger with build-in precise amperometer. At the beginning of charging process amperometer schowed 8-9 ampere. After a few hours of charging, when amperometer was alredy very near to 2 ampere and it didn't want to swich to smaller batterie by itself, i decided to turn the ignition key to second position for a moment, that means to this position, when all controll lamps were lightning. In that moment i heard a quiet "click" and amperometer schowed me promptly again 7-8 ampere! So, if you want to charge both batteries, you must "support" your car electronic a little bit, by helping him manually...
Greetings from frozen north-east Poland, where we have today approximately half a meter of snow and -8 degrees Celsjus
Andrzej

[AnttiS]

Would it be posssible to put in two 353 mm long batteries i.e. something like Varta Ultra Dynamic 95 Ah ones?

[Erich]

Annti:
be careful with bigger batteries. I tried to install one bigger size in my E32 750iL under the rear seat, only 15 mm higher, but I could not completely fit the electric rear seat. Had to change again to the smaller one.
Varta states for the E38 750
Länge [mm] 353 length
Breite [mm] 175 width
Höhe [mm] 190 height
Also note where the plus and minus poles are, there are different versions, and also the hose for the drain of gases and acid.
Here are some details
 http://www.varta-automotive.de/index...plication.html
If you do not use the car so often, maybe you make it like I do with my Highline. I bought a cheap solar battery charger. That does not recharge a drained battery but is maintains it. Just connect one with each battery and place it on the dash. But of course you need some sunlight for that
A blocking diode prevents a reverse flow of energy.
 http://www.batterystuff.com/solar-chargers/

[AnttiS]

Erich,

In my car the batteries are in the trunk inside the right fender on top of each other.....that's what the owner's manual tells.

Antti