Thread: Lithium Battery anyone?

If the vehicle has a smart alternator,which it probably has,lithium is not the way to go.
A search on here will reveal other threads on Lithium batteries for late model LR's.

Have a read of this thread from the L494 forum:

Fitted LIPO4 Starter Batteries

Originally Posted by scarry

If the vehicle has a smart alternator,which it probably has,lithium is not the way to go.
A search on here will reveal other threads on Lithium batteries for late model LR's.

I tried searching, I really di, but I just don't ever seem to find what I am looking for. I used to be an active member over on bimmerboard.com when I had my beloved 7 series BMW but it will likely take me a while to become familiar with this site.
Thanks everyone for your help.

Have you had your earth lead connection recall done? I had the same issues until they finally installed the new earth lead connection to the body. I had two replacement batteries in the first year - mine is a late 2019 so it spent most of the first two years in lockdown in the garage here in Melbourne.

These so-called "smart" alternators are a pain. I can drive for 8 hours, non-stop, at 110 km/h and the battery is still under 80% charged. My auxiliary lithium battery, on a DC-DC charger, is always at 100%.

I have found that leaving the car unlocked in the garage keeps the state of charge much higher than locking or double locking it. When locked or double locked I had to put it on a charger every week or two. Unlocked it is fine for months. Go figure...

The joys of modern cars.

Cheers
Numb Thumbs

If you have a diagnostic tool that can do it, set the battery indicator to a new battery so that smart charging doesn't reduce charging for an older battery.

its not good for lithiums to be pushed to 100% every day, (like agm's and lead acid). Its a thing we need to get our collective heads around.

Has anyone experimented with placing a DC/DC charger between the alternator and Lithium battery?
I would think a 50amp DC/DC charger would surely keep the battery fully charged even with a smart alternator.
Even if the alternator was charging at say 12 volts the DC/Dc charger would boost it up to 14.4-14.6 V.
In any case I would think that the load of the charger would cause the alternator to up its charge rate.
I don't know what the ECU would think of that but perhaps some sparkie on the forum could nut it out.
Regards PhilipA

Originally Posted by PhilipA

Has anyone experimented with placing a DC/DC charger between the alternator and Lithium battery?
I would think a 50amp DC/DC charger would surely keep the battery fully charged even with a smart alternator.
Even if the alternator was charging at say 12 volts the DC/Dc charger would boost it up to 14.4-14.6 V.
In any case I would think that the load of the charger would cause the alternator to up its charge rate.
I don't know what the ECU would think of that but perhaps some sparkie on the forum could nut it out.
Regards PhilipA

Hi Philip and you must NEVER have your motor running without having a battery, lead acid or lithium, connected to the alternator.

Disconnecting the cranking battery while the motor is running can very quickly lead to your vehicle’s electronics being damaged or destroyed by the the alternator’s VERY high voltage spikes.

The cranking battery in all vehicles acts as a huge voltage spike suppressor, filtering out the 60+v spikes that all alternators creat in normal operation.

I suspect this is the reason lithium batteries are not used by vehicle manufacturers as cranking batteries, because lithium batteries can shutdown in over voltage situations or if they are discharged to low.

Even a lead acid battery with a dropped cell will still act as a voltage spike suppressor because it is very rare for a lead acid battery to go OPEN CIRCUIT but it is common place for faulty lithium batteries to go open circuit.