I believe the manual recommends 65 Amps?
How would a 71 Amps battery fare?
What about 90 Amps, would that be to much and burn something?
Any suggestions as to what the perfect battery would be?
What is...
What is...
The best battery and the best Amps for a battery for the E12 with AC?
I believe the manual recommends 65 Amps?
How would a 71 Amps battery fare?
What about 90 Amps, would that be to much and burn something?
Any suggestions as to what the perfect battery would be?
I believe the manual recommends 65 Amps?
How would a 71 Amps battery fare?
What about 90 Amps, would that be to much and burn something?
Any suggestions as to what the perfect battery would be?
Last edited by Domingo on Wed Sep 14, 2011 8:05 pm, edited 1 time in total.
I have installed 75Ah battery on mine e12 (2.8i engine, without AC).
Talking about 90 Ah - I'll say - it's OK if it fits mechanically, but 75-85 Ah is enough.
The PROs - will last longer, because the maximum load current is higher, compared to 65 Ah battery for example. Bigger battery will cope with the starter current much easily, without battery cells overcurrent degradation.
Better starting in cold weather. If you have additional high power audio - it helps.
The CONs - 90 Ah battery is more expensive. It is heavier, but this is not so important (you can install it in the trunk, but this is another story).
There is no danger to burn anything, if you do not allow deep discharge of the 90 Ah battery. The only concern then is the higher charge current, drawn from the alternator. This is one of the reasons to install bigger air cooled alternators (for example 110 Ah)
Talking about 90 Ah - I'll say - it's OK if it fits mechanically, but 75-85 Ah is enough.
The PROs - will last longer, because the maximum load current is higher, compared to 65 Ah battery for example. Bigger battery will cope with the starter current much easily, without battery cells overcurrent degradation.
Better starting in cold weather. If you have additional high power audio - it helps.
The CONs - 90 Ah battery is more expensive. It is heavier, but this is not so important (you can install it in the trunk, but this is another story).
There is no danger to burn anything, if you do not allow deep discharge of the 90 Ah battery. The only concern then is the higher charge current, drawn from the alternator. This is one of the reasons to install bigger air cooled alternators (for example 110 Ah)
The answer is to buy the largest cranking capacity that will fit in the space designed for the E12 at the lowest cost.
Rant - 'wet' batteries are at best hit and miss, I've paid excessive bucks in an emergency for an Interstate that lasted three years and less for a big box 'Everlast' that did indeed outlast the more expensive flavor. Do a research on how batteries are manufactured, and what happens to them over their lifespan; when a cell finally shorts, it's toast no matter what the age.
Caveat Emptor
Rant - 'wet' batteries are at best hit and miss, I've paid excessive bucks in an emergency for an Interstate that lasted three years and less for a big box 'Everlast' that did indeed outlast the more expensive flavor. Do a research on how batteries are manufactured, and what happens to them over their lifespan; when a cell finally shorts, it's toast no matter what the age.
Caveat Emptor
HTH
'80 528i
'80 528i
-
thomas_m535i
- Posts: 98
- Joined: Tue Jul 21, 2009 7:22 am
- Location: The Netherlands
Yep, I agree with the posts above.
Most premium brand batteries would suit your purposes fine. I have good experiences with Optima batteries (http://www.optimabatteries.com/home.php). These batteries are spill-proof (which is good), very durable, and have good cold-starting characteristics (which can be nice when it's winter in The Netherlands).
Good luck with the battery hunt.
Most premium brand batteries would suit your purposes fine. I have good experiences with Optima batteries (http://www.optimabatteries.com/home.php). These batteries are spill-proof (which is good), very durable, and have good cold-starting characteristics (which can be nice when it's winter in The Netherlands).
Good luck with the battery hunt.
E12 M535i '80 (currently restoring)
