Battery Maintenance/Float Charger Connected While Battery is Removed

[upallnight]

Even those these are maintenance free batteries, they all use a water electrolyte. Most likely the electrolyte is low so that the lead plates are exposed to the air. On some batteries there are caps or section at the top of the battery that can be pried off and new DISTILLED water added. DO NOT use any type of water other then DISTILLED WATER.

[StephenVA]

[QUOTE=jim628;1014145]

Originally Posted by Qsilver7

Double ditto bcredliner on the above quote. That's the ONLY time I use my charger's 50 amp setting. Its when the battery is dead, and I need to get the vehicle started NOW...and hit the road.

Hi,
When you did this, did you:

A) Start the engine while the 50 AMP charger is still connected and charging
or
B) Connect the 50 AMP charger, wait few mins, disconnect the 50 AMP charger then start the engine


Thanks.

If "A" insert credit card. (This quiz was too easy). Now if anyone says "yes" they did, then read below:

If this option is selected and you will "shock" the electrical system, all bets are off on everything surviving the surge. Alt, regulator, control module, etc. Kind of like jump starting car A while car B is running or is at a high high RPM. This is another automotive skill no longer taught in high schools.
Winter is coming so this will be a daily event in office parking lots all over the Rust Belt. Repair shops love the business.

[Qsilver7]

Originally Posted by jim628

Hi,
WHen you did this, did you:

A) Start the engine while the 50AMP charger is still connected and charging
or
B) Connect the 50 AMP charger, wait few mins, disconnect the 50 AMP charger then start the engine


Thanks.

I did "B". I have a gauge on the charger...and when using the 50 amp "boost charge" I leave it connected until the gauge registers it's okay. Then I removed the charger from the battery posts before starting the car.

Unless you're really committed to buying only BMW or MB batteries...you can use just about any 49/H8 or 95R/H9 class size battery. Most battery brands in the USA are made by the same 3 battery manufacturers (Johnson Controls, Exide, East Penn). You can see in the chart below what the specs are for the East Penn 49/H8 & 95R/H9 batteries are. The ones mfg'd by JC & Exide have pretty similar specs. The warranties may vary by brand label...but again, are usually 2 or 3 years...many times with an extended pro-rated warranty after the initial full replacement years.




I've always suggested checking your local autoparts stores like Autozone Advanced Auto, O'Reillys, Pep Boys etc...then there's Batteries Plus, Sears, Walmart, Interstate Battery outlets/stores, etc. Again, your looking for the 49/H8 or 95R/H9 battery class size. This will be the equivalent of the usually $200+ BMW branded battery. You can also decide if you want lead acid or AGM...either will still need to be vented (so be careful not to lose or pull the X5's vent tube out...you'll need to reuse it and the little elbow).

Here's some examples of replacements:

Autozone Duralast Battery Brands








Sams' Club Duracell Battery Brands:








Batteries Plus Duracell Battery Brands:

[Qsilver7]

[QUOTE=StephenVA;1014154]

Originally Posted by jim628

If "A" insert credit card. (This quiz was too easy). Now if anyone says "yes" they did, then read below...

WHEW! Glad I picked B.

[bcredliner]

[QUOTE=StephenVA;1014154]

Originally Posted by jim628

If "A" insert credit card. (This quiz was too easy). Now if anyone says "yes" they did, then read below:

If this option is selected and you will "shock" the electrical system, all bets are off on everything surviving the surge. Alt, regulator, control module, etc. Kind of like jump starting car A while car B is running or is at a high high RPM. This is another automotive skill no longer taught in high schools.
Winter is coming so this will be a daily event in office parking lots all over the Rust Belt. Repair shops love the business.

The reason for the boost setting is provide enough current for the starter motor. It is OK to leave the charger connected until the car starts. It is also OK to increase the RPMs of the car providing current. At peak output the alternator is only putting out 14-17 volts.

[jim628]

Hello:

Thanks again for all your comment. First I bought a Schumacher 50-10-6<>2 AMPS charger (SE 5212A-CA). I tried to charge my old battery unfortunately the battery is no longer able to hold electricity. After it is fully charged, few mins later the voltage keeps dropping to around 11 Volts. After several attempts, i conclude the battery is dead. As for the charger, i will keep it for future use. It has a jump start feature so i will need it someday.

So i decided to get an Interstate battery which has a slightly higher CCA then the standard battery from BMW. There is an interstate battery dealer in my area so i only paid $191.95. The battery is slightly wider than the original one but it fits in the battery compartment. Looks like the battery compartment is designed to accommodate 3 different battery sizes and this interstate battery fits the medium size.


Here is the spec of the battery (Interstate Batteries | Every Battery for Every Need)

Retail*: $191.95
List: $218.95

Mega-Tron Plus
Mega-Tron Plus 49/H8 Automotive Battery Six-Year Performance 730 CCA
30 Month
Free Replacement
Six Year
Performance Warranty
730 CCA (Cold Cranking Amps)
Part # MTP-49/H8

[Qsilver7]

Thanks for the update...I hope you hooked the battery up to the vent tube.