Safe to use battery maintainer on 12V?

[Electryic]

Would anyone know of any issues in connecting a battery maintainer to the 12V? Car is only used for occasional short trips and the 12V is bit low, i have a very nice 12V battery maintainer that is supposed to bring the battery back to full capacity, I am wondering if there is any reason anyone is aware of that I should not use it (i.e. sending any kind of small voltage back through the charging system etc).
Another option, I would guess would be to disconnect the connections before hooking up the battery maintainer, but I would like to avoid having to do that if possible and/or there is no risk of connecting battery maintainer with the battery connectors still connected. Thanks!

 

[LeftieBiker]

Welcome. Many of us use battery maintainers to make up for our Leaf's shortfall in charging the 12 volt battery. It isn't a problem, although if you connect the maintainer ONLY while the car is actively charging, it may be 'fooled' into 'thinking' that the battery is full, because of the 13 or so volt charging current.

 

[thew]

Yup, been doing it since 2011. I leave the Battery maintainer on it anytime i am going to be away for more than a few days. And in that Case i Disconnect it from the EVSE dock after the Traction Pack is fully charged. It will not cause an issue if you leave the 12 volt maintainer plugged in while the system is plugged into the EVSE dock. It makes no difference to the EVSE Dock Charging the Traction Pack. The System will just not send voltage to the 12 volt battery because the maintainer will be fooling the EVSE dock into seeing that voltage.. The Car will still fully charge the Traction pack. But if you are going to leave it a few days just unplug the EVSE and leave your 12 volt maintainer on .

 

[cwerdna]

If you search https://mynissanleaf.com/search.php?keywords=optimate&terms=all&author=cwerdna&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search, you'll see I used to use an Tecmate Optimate 4 charger which charges then maintains on my former '13 Leaf. I never had an issues w/me leaving the battery connected to the car while using that.

 

[Electryic]

Thank you for the replies!

 

[transamhun]

I'm using CTEK MXS 5.0 for this purpose on various EV cars, never had a problem with it.
Not sure if it's available in the U.S. though.