[rikwynnpa]

My Z4 will be in the garage for several months so i bought a BMW battery conditioner that I have hooked up to the car. Any thoughts?

[Combatcrew2]

I bought a Maypole one. I don’t leave it connected all the time though. Every couple of weeks I connect it to bring it back to 100% charged.

[badfitter]

Good to have a battery maintainer that has a setting for AGM batteries, assuming your Z has AGM. My 2021 has an AGM battery and I use a CTECK.

[Amadeo]

Originally Posted by badfitter

Good to have a battery maintainer that has a setting for AGM batteries, assuming your Z has AGM. My 2021 has an AGM battery and I use a CTECK.

Change your battery maintainer connections to the engine bay battery poles. If you keep using direct connection to the battery in the trunk you will ruin your battery because the onboard computer will not recognize the external charging. Since charging didn't take place from the the engine bay, computer will get wrong data and battery optimal charge will be compromised.
Check previous post on this subject. Check ctek charger threat.

[badfitter]

Originally Posted by Amadeo

Change your battery maintainer connections to the engine bay battery poles. If you keep using direct connection to the battery in the trunk you will ruin your battery because the onboard computer will not recognize the external charging. Since charging didn't take place from the the engine bay, computer will get wrong data and battery optimal charge will be compromised.
Check previous post on this subject. Check ctek charger threat.

I see that this might be an issue if your battery is discharged frequently and recharged via the battery maintainer. However, since my battery is fully charged when I hook up the CTEK, the maintainer is only providing for "battery leakage" and the very minor phantom loads of the car. It is normal for the car to understand a healthy battery and this is what the direct connection maintains.

Of course my car only sits for 2-3 weeks at a time so this really is not an issue. I'll certainly report back if I experience any strange conditions.

Thanks.

[German1967]

I have the CTEK 5.0 (the BMW is a branded CTEK). Used it for the first time this winter and was surprised how long it would take to fully charge the battery (about 20 hrs across all 7 phases). I am using it now every other week to top off the battery when I am not driving given current weather conditions.
As mentioned before, the charger should not be connected to the battery directly but to the terminal poles in the engine bay to not confuse the battery management system.

[CaboM4]

Originally Posted by German1967

I have the CTEK 5.0 (the BMW is a branded CTEK). Used it for the first time this winter and was surprised how long it would take to fully charge the battery (about 20 hrs across all 7 phases). I am using it now every other week to top off the battery when I am not driving given current weather conditions.
As mentioned before, the charger should not be connected to the battery directly but to the terminal poles in the engine bay to not confuse the battery management system.

+1

I use the same CTEK-branded AGM conditioner on both my G29 and F55 which are sitting dormant in my garage until the spring weather arrives. Works great, and much less expensive than the BMW re-branded version of this CTEK charger

[sanfordrich]

Just saw this post. I have my trickle charge directly connected to the battery posts. Based on some of the opinions here, I probably need to change, although so far, no problem. It was on the trickle charge all last winter and now this winter. I hope the post by badfitter above is true. Finally, I assume the standard battery in the 2020 Z4 M40i is an AGM battery based on the posts. I don't think the trickle charge I am using has a special setting for that type of battery. Will this also be a problem? Inquiring minds want to know...ha, ha.

[StanDiego]

Originally Posted by rikwynnpa

My Z4 will be in the garage for several months so i bought a BMW battery conditioner that I have hooked up to the car. Any thoughts?

Have any of you installed a quick disconnect to the engine bay battery terminals?

I have a NOCO charger with optional eyelet terminals that I've used in previous vehicles to be able to quickly connect/disconnect the charger without having to pop the hood (by running the eyelet terminal cable to/near the front grill area). NOCO accessories

The battery terminals in the G29 appear to make this a greater challenge. I'm hoping to hear from someone who has come up with a solution.

[COKen]

Originally Posted by StanDiego

Have any of you installed a quick disconnect to the engine bay battery terminals?

I connected mine to the battery ports under the hood.

[ebirotedu]

Revivication of this thread reminded me to purchase a CTEK charger (the non-BMW 5.0 model with a pigtail connector plug) for my Z4. This Saturday will be the 2nd time in as many weekends that it's cold here in ATL and I probably won't drive it.

My KTM 1290 SAS spends the entire year plugged into a CTEK, whether I'm riding it or not.

[StanDiego]

Originally Posted by COKen

I connected mine to the battery ports under the hood.

Where did you route the cable to?

[COKen]

I just ran it over to the inside of the fender (under the brace) on the passenger side. The connector is behind the headlight.