Will a battery recharge help temporarily?

I am fairly certain my wife’s BMW X1 needs a new battery, but cannot get into NTB for another couple of days. If I give the battery a bit of a boost with my external charger for the next two nights, will that help prevent her from getting stuck during routine errands? Just to “top off” the voltage? Or is that pretty much a waste of time?

The resting voltage is showing up as 12.3v. The car is never in the shade and we live in record-hot Texas. It’s a 2018, so it’s about time for a new battery. The primary symptom is a sporadically sluggish start.

If the charging system is working, then there should be no problem just driving it as is.

It sounds like low cranking amps is what’s causing the sluggish starts.

This chart indicates the state of charge of the battery.

RV Tech Library - Battery Charge Voltage


Charging it will help short term but if your car has the little black box with a wire on the negative terminal ( it should do but I’m not sure on US spec) that unit is the intelligent battery sensor, and monitors the level of charge of the battery and the alternator tries to keep it a small amount above what it needs to start (saves gas on unnecessary charging) so it won’t replace all the charge you’ve put in.

Can NTB properly register the battery to the car? If not, you really should go to the dealer or a shop that can.

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Most shops have the equipment to register batteries to vehicle.


Yes, should help, but not guaranteed to work. 12.3 volts (measured before first start of the day) means battery is very close to no-good. If 12.3 volts measured soon after 10 mile drive& parked, battery can’t be counted on to crank engine, very iffy.

Better stay by the phone anyway for a rescue. Battery died on the wife’s key fob but she luckily got it to start the car. Otherwise it was a ten mike trip for me.

They don’t like to be stalled. Years ago she had a blowout before phones and before I would have gone looking for her. A nice group of guys stopped. Next day four new tires. All I have to do is mention a tire is getting worn now and no argument to put new ones on. Trying to figure how to build on that for getting gas and checking oil