[riverol]

I have read the E90 battery threads, posts and DIY, from which I gathered the 2007 335i came with a Group 94R battery. I looked up P/N 61216946334 on my factory battery at RealOEM.com which read "Exide" and "Ended". From this I gathered ther factory battery was made by Exide but is now discontinued. I found an Exide made ProLine Platinum 94R at Pep Boys with a white case identical to that of the factory battery in my car, but 12 inches long, 765 CCA and 140 RC, instead of 14 inches long, 90AH 720A and 160 RC for the factory battery in the car. Please, can anyone point me to the right Group number (Group 49?) and where I can find a battery for the car, conventional or AGM? Thank you.

[hugus311]

that is the right size. I recently swapped out battery to 94R size. It is true that it is smaller but that is irrelavant because the hardware that holds the battery down has a hole to screw into for the smaller size. I got my battery at wal-mart . 3 year free replacement and 6 year prorated for 80 bucks.

[GoRomeo]

Hi there can u give me the part number, brand etc... i need to get a battery at walmart? I have an e90 2006. I need one i think. The battery icon turns on whenever i try to listen to the radio with engine off. Thanks in advance.

Originally Posted by hugus311

that is the right size. I recently swapped out battery to 94R size. It is true that it is smaller but that is irrelavant because the hardware that holds the battery down has a hole to screw into for the smaller size. I got my battery at wal-mart . 3 year free replacement and 6 year prorated for 80 bucks.

[hugus311]

Walmart's Everstart Maxx-94

http://www.e90post.com/forums/showth...=292200&page=2

DIY
http://www.e90post.com/forums/showthread.php?t=292200

The 94R has a reserve capacity of 155 mins and amp hour rating of 85aH. Its a 950 CA and 850 CCA battery.

The stock BMW 94R battery is rated at 140 mins RC and 80aH with 720CC and 720CCA.

Also comes with a 3YR free replacement warranty.

You should register it. I didnt, no issues has of yet

I picked mine up for $82 + $9 core.

[riverol]

As per recommendations here at bimmerpost, bimmerforums, etc., I went to Walmart and Costo, but in this neck of the woods they stock only more common group sizes like 34 and 65. Pep Boys has a 94R Platinum with the same as the OEM (Exide, as per RealOEM) battery in the car, two inches shorter, more or less like specifications, $150, less $30 discount, $120. Also as per recommendations in posts and DIY, today I checked Autozone and found the Duralast Platinum 8H (49 group size) AGM for $164 and the 49 Duralast for $104. Both have better specifications than the OEM battery in the car. As per posts, the Duralast Platinum 8H AGM should last longer than conventional batteries and be cleaner (no venting needed), with registration and programming. As I will have a Bavarian Technic tool here soon, I will check its registration and programing capabilities. If these can be done, I think I will go for the Duralast Platinum 8H AGM. Otherwise, the 49 Duralast. BTW, the Pep Boys battery was manufactured back in January, so it has been sitting about 6 months. Again, thank you for your replies and I would like to hear your comments.

[riverol]

BMW OEM battery in the car has the indicator that shows green (good), black (recharge) or yellow (replace). It shows black. I have charged the batery for hours with a fairly smart Shumacher X103 charger. The charger shows about 80% charge and 12.5 V when I connect it to the battery. The charger starts charging at around 13 V, slowly goes up to 16 V, and in an hour or so shows 100% charge for the battery. Then the charger alternates between off and on at around 13 V, as the battery goes to 100% charge, down to 95% slowly and back up to 100%. But after I disconect the charger, the battery goes back to about 80% and 12.5 V. The indicator remains black, with a few glimpses of green when charging. Should I keep charging? Any comments?

[hugus311]

place load tester on battery, as voltage is sometimes misleading when trying to determine a batteries condition. Also if you go the agm route you will need to program at dealer because the bt tool only has registaring process. If you donot reprogram the car the charging system will overcharge and could cause it to explode.

[fdriller9]

Originally Posted by hugus311

place load tester on battery, as voltage is sometimes misleading when trying to determine a batteries condition. Also if you go the agm route you will need to program at dealer because the bt tool only has registaring process. If you donot reprogram the car the charging system will overcharge and could cause it to explode.

It won't explode....

It will decrease life expectancy....

But OP, he's right. If you retrofit an AGM you'll need to have the battery programmed, then registered. I had mine done with an autologic tool at an indy.

Lowest AGM profile in our cars is 70aH (70aH-100aH AGM or 56aH - 100aH non-AGM, Leadacid).

[riverol]

As far as I can tell, battery is fine except for the black eye that indicates a charge is required. Thre is no sign of yellow to indicate it is defective. It is not green either to indicate it is good. I wonder whether to continue to charge it hoping for the green eye. Thank you letting me know the BT too will not reprogam. There is no question of going to the dealer here, even if they paid me. Whether at idle or 2000 rpm, the alternator charges the battery at 14.2 V, within the limit for AGM battery charge. Do you think the AGM could still be overcharged or even explode?

[fdriller9]

My car doesn't go above 13.9v programmed as a 70aH AGM....usually hoovers around 13.8v.

[hugus311]

Originally Posted by riverol

Do you think the AGM could still be overcharged or even explode?

wont explode. pardon me misspoke. with. programming the current charging cycle will severly shorten the life of your agm battery should you go that route

[riverol]

Fluke multimeter shows alternator charging at a steady 14.2 V, from idle to 2000 rpm, well within the limit of 14.8 V charge for AGM batteries. Can you think of an scenario in which the alternator would charge over 14.8 V?

AGM batteries have pressure relief valves, so they should not explode when overcharged. But then they would release perhaps corrosive gas into the trunk of the car with accompanying damage. Battery life would then be shortened. Overcharge would counter the advantages of cleanliness and durabilty of AGM batteries.

As noted, my car now charges at 14.2 V. If anyone can think of an scenario in which it would charge above 14.8 V, then I will put in the car a conventional battery, with equal or better specifications than OEM, BMW (Exide) Group 49, 90 AH, 720 A. Costco, Walmart, BMW dealer and independent BMW shops are not options for me here. Autozone has the Duralast Platinum H8 AGM and conventional Duralast Gold H8. Advance Auto Parts has a conventional Gold 49/H8. Bavarian Technic tool will be here soon and I will see what I can do with it.

If anyone can tell me what governs alternator output, please do. Thank you.

[fdriller9]

There are multiple charging profiles within our cars and that will govern the alternator output.

The output should be around 14.7v. Before I swapped my non-AGM battery, my alternator was putting out 14.7v. Now it's around 13.8v programmed as a 70aH AGM.

I don't think AGMs have pressure relief valves. Lead acid batteries have a vent valve and there is a connection on front side of the battery (front being closest to the engine bay.)

My AGM is sealed.

[riverol]

I tested alternator output again. It was never more than 14.2 V from idle to 3,000 rpm. Then, I tried with low and high beams on, A/C on high, etc., and it rose to between 14.3 and 14.4 V. I think this is within the limit of 14.8 V for AGM batteries. But I am not knowledgeable. I have only read BMW fora, Wikipedia, etc.. This is where I read that AGM batteries are valve relief lead acid (VRLA) batteries. From Wikipedia, www.RealOEM.com and www.getbmwparts.com, I gather BMW favors AGM over conventional batteries since 2007 and has discontinued use of conventional batteries in favor of AGM for the 335i. As the car runs fine with the factory battery, I am waiting for the BT tool to arrive (perhaps tomorrow) before I get a new battery, either conventional or AGM, but it will be:
Group#49/EN size 88L5/DIN H8, OEM for my car, as much battery as will fit in, with a bit better specifications than OEM at 100 Ah, 900 CCA @0 degrees and 185 RC

[kaigoss69]

Originally Posted by *********

It won't explode....

It will decrease life expectancy....

But OP, he's right. If you retrofit an AGM you'll need to have the battery programmed, then registered. I had mine done with an autologic tool at an indy.

Lowest AGM profile in our cars is 70aH (70aH-100aH AGM or 56aH - 100aH non-AGM, Leadacid).

What do you mean when you say that the battery needs to be programmed? I am familiar with registering the car, but not battery programming. My battery is dead so I need to get a new one. Is the Agm the better one to get?

Also, which size fits better 48 or 94R? In my old car (06 330i) I put in a size 48 from walmart. Never had any issues with it.

I have the bt tool now, so I can register the new battery after installation to make sure it will be charged properly.

[mthomas]

BT tool will only register a new battery, it will not tell the charging system if you change battery types. Replace with the same type and capacity if you are using the BT tool. If you want to change type or capacity you need to have someone reprogram for that battery.

[fdriller9]

Originally Posted by kaigoss69

What do you mean when you say that the battery needs to be programmed? I am familiar with registering the car, but not battery programming. My battery is dead so I need to get a new one. Is the Agm the better one to get?

Also, which size fits better 48 or 94R? In my old car (06 330i) I put in a size 48 from walmart. Never had any issues with it.

I have the bt tool now, so I can register the new battery after installation to make sure it will be charged properly.

There are numerous charging profiles our cars can be programmed to activate. These programs will properly charge and maintain the battery you install to extend life and upkeep performance.

Not sure which which size fits better. I retrofitted a 21lb Braille battery so it's quite smaller and half the weight of the OEM battery.

AGM's are good for those who drive short distances. They have slightly better performance and although some have a lower CCA rating, they supposedly perform better in the cold. They are also sealed units and do not vent as lead acids do.

Here's a write I did awhile ago:

http://www.e90post.com/forums/showthread.php?t=473109

I wouldn't recommend getting the Braille. It has been working fine for me but it does take a second or 2 longer to crank in the winter because of the lower Ah and CCA rating...otherwise it performs just fine.

But if you do want to retrofit an AGM, just get one with a higher CCA and Ah rating. Similar to to your stock battery.

Basically, programming activates a charging profile. The user chooses which one to activate based on which battery is being installed.

Registration is explained in the thread I linked to but it basically tells the car a new battery has been installed.

As a battery ages it's ability to hold a charge deteriorates. Our cars will take this into account when maintaining the battery so it doesn't overcharge it nor waste power charging a battery that won't hold that energy.

Originally Posted by mthomas

BT tool will only register a new battery, it will not tell the charging system if you change battery types. Replace with the same type and capacity if you are using the BT tool. If you want to change type or capacity you need to have someone reprogram for that battery.

Yes, spot on.

[kaigoss69]

Originally Posted by *********

There are numerous charging profiles our cars can be programmed to activate. These programs will properly charge and maintain the battery you install to extend life and upkeep performance.

Not sure which which size fits better. I retrofitted a 21lb Braille battery so it's quite smaller and half the weight of the OEM battery.

AGM's are good for those who drive short distances. They have slightly better performance and although some have a lower CCA rating, they supposedly perform better in the cold. They are also sealed units and do not vent as lead acids do.

Here's a write I did awhile ago:

http://www.e90post.com/forums/showthread.php?t=473109

I wouldn't recommend getting the Braille. It has been working fine for me but it does take a second or 2 longer to crank in the winter because of the lower Ah and CCA rating...otherwise it performs just fine.

But if you do want to retrofit an AGM, just get one with a higher CCA and Ah rating. Similar to to your stock battery.

Basically, programming activates a charging profile. The user chooses which one to activate based on which battery is being installed.

Registration is explained in the thread I linked to but it basically tells the car a new battery has been installed.

As a battery ages it's ability to hold a charge deteriorates. Our cars will take this into account when maintaining the battery so it doesn't overcharge it nor waste power charging a battery that won't hold that energy.



Yes, spot on.

Thanks for the reply and the informative thread you posted! Also thanks to the OP of this thread and the information that was provided by other forum members.

I took my old battery out and took it with me to Walmart. I was looking for the 94R battery but could not find it. Then I found an Everlast Maxx-H8 14 battery that had the exact same dimensions as the original one. The little computer on the battery rack also confirmed that the H8 was the right one. Took it home and installed it. It was a perfect fit. Vent hole was in exact same location, however there was another one on the opposite side. I put some wood putty in there just to be sure the gases go out the tube and not the hole on the other end. The Walmart battery has 760 CCA compared to the original battery's 720 CCA so I am good there. Unfortunately, I could not find any additional specs such as the Ah and RC rating of this battery but I suspect since it's the same size and the computer says its the right one, I should have nothing to worry about. Immediately after installation, I did the battery "reset" with the BT tool.

All in all this cost me $98 for the battery and about an hour of removal end reinstall. Not bad at all. Here's a picture of the two batteries side by side.

[K20A2_S]

^^I went with the autozone duralast gold 94R-DLG one, $150....3.yr full replacement, 8 yr pro rated......used some putty they had to seal cracked gas tanks, so I figured its good enough to use to block the other vent without a tube.

No codes so far, didn't even lose my presets on radio.......just had to set time again.

[John 070]

Bottom line, on my Nissan, I got one of those batteries with the huge CCA and huge RC numbers, and it failed in 24 mos. got a replacement free and it failed in 18 mos. Conclusion? Not a good battery.

The original lasted 6 years, and had filler caps.

Since the BMW needs registration, imho even more reason to get a decent battery. My OEM came out after 5 yrs., I still have it, and it passes a load test even after 3 wks of sitting in the garage. So I paid $170 for the OEM, maybe that's double what a battery goes for in Wal Mart, but imho I know what I got. just my .02

[John 070]

Originally Posted by K20A2_S

^^I went with the autozone duralast gold 94R-DLG one, $150....3.yr full replacement, 8 yr pro rated......used some putty they had to seal cracked gas tanks, so I figured its good enough to use to block the other vent without a tube.

No codes so far, didn't even lose my presets on radio.......just had to set time again.

Sounds like it cost the same as OEM, give about $20.

[John 070]

Originally Posted by kaigoss69

Thanks for the reply and the informative thread you posted! Also thanks to the OP of this thread and the information that was provided by other forum members.

I took my old battery out and took it with me to Walmart. I was looking for the 94R battery but could not find it. Then I found an Everlast Maxx-H8 14 battery that had the exact same dimensions as the original one. The little computer on the battery rack also confirmed that the H8 was the right one. Took it home and installed it. It was a perfect fit. Vent hole was in exact same location, however there was another one on the opposite side. I put some wood putty in there just to be sure the gases go out the tube and not the hole on the other end. The Walmart battery has 760 CCA compared to the original battery's 720 CCA so I am good there. Unfortunately, I could not find any additional specs such as the Ah and RC rating of this battery but I suspect since it's the same size and the computer says its the right one, I should have nothing to worry about. Immediately after installation, I did the battery "reset" with the BT tool.

All in all this cost me $98 for the battery and about an hour of removal end reinstall. Not bad at all. Here's a picture of the two batteries side by side.

Have you load tested your old battery? My car is an '07 and I proactively changed it in Dec., but kept the old one. It passed load tests after one day, three days, three weeks, so it's still good. My wife's aunt has a '06 330i and the battery is still good.