Very interesting. I got interested in these when I got my jump starter pack with LIon batteries and it started the Mercedes faster than the factory Varta. Really opened my eyes, and I'm well pleased to see this technology evolving.

We have had some here in Australia promoted as suitable for off road use, but they don't seem to last long before they're down to 50% capacity. Seems that Australian under bonnet temperatures are too high for them and they degrade rapidly above 60º C. Very expensive too.

I'm thinking about putting a LiFePo4 under the passenger seat for a house battery, where it can stay cool. I gather you have yours installed as a starter battery - I will be interested to hear how yours goes in your cooler conditions, sounds like a good match so far.

Interesting.
Can you recycle old Li- ion batteries?
You get back money back for your old lead/acid battery at metal recyclers - 95-99% of a lead car battery can be recycled. Jules

Even though the Freelander has a brilliant design to circulate air to cool the battery while keeping it separate front the engine bay (putting dust issue aside, nevertheless very good).

As others have pointed out ambient temperature in Australia is a killer of batteries.

The starter motor on the Si4 requires 238amps. Diesel I suspect a bit more. Let's say 280 amps.

More to the point, Lithium batteries can't cope with this load unless you are using a Victron, even then it's a bit thin.

I have 4 x 26AH gel batteries for accessories (& jump starting), combined can do 1040amps for running compressors (360amps for 5 minutes) & jump starting a few too many times other cars, more so in our street, no one other than me has jumper leads.

Not to forget that if you basically drain a lead acid battery once a month, that it is only 60 of 300 full cycles. The battery still has the bulk of its 4 to 5 years & will not fall off a cliff (look at the total AH draw of the total of the battery). Don't stress using only 30% or so of the battery's AH & every now & then 100% of the battery's capacity. A lead acid battery is designed to be used to 100% capacity, every now & then.

P.S. Unless the lithium battery has Winston lithium cells I would recommend a gel battery for backup.

P.P.S. The cheap lithium batteries are packed with foam. Look at "battery teardown". Procrastination, mankind's greatest labour saving device!

Acoustic insulation ARB TPMS 3xARB air compressors After cooler Air tank On-board OCD pressure air/water cleaning Additional 50L fuel Carpet in doors ABE 2x1kg Waeco 28L modified fridge Battery 4x26ah Solar 120w Victron MPPT 100/20 DC-DC 18amps 175amp jumper plug Awning 6x255/60R18

jules wrote:

Interesting.
Can you recycle old Li- ion batteries?
You get back money back for your old lead/acid battery at metal recyclers - 95-99% of a lead car battery can be recycled.

I wonder what the BMS or Battery Management System makes of it? Do you need a reset? 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE

That's a good question. LifePO4 has very similar voltage characteristics to lead acid. I don't know how the electrical system will respond when the battery's own BMS shuts down charging when the battery is full. A lead acid will naturally reduce charge current as it approaches fully charged, but it'll still absorb some current, which results in gassing.

However a LifePO4 battery must terminate charging when full, which the internal BMS does by literally disconnecting the cells from the charge current. I don't know how the vehicle electrical system will respond to the battery being disconnected when charged.
While I love the LifePO4 chemistry, I'm not sure it's suitable as a retrofit to a previous lead acid based power system. 2009 Rimini Red SE TD4. Soon to be sold.
Hyundai Ionic 5 Ultimate on order.
Gone. 2006 Tonga Green i6 HSE.

I always understood that you needed a different battery charger for lithium batteries (for example for mobility scooters)

Mr Google says
Lead acid battery chargers typically deliver a constant voltage charge, while lithium-ion battery chargers typically deliver a constant current and constant voltage charge. This means that lithium-ion battery chargers are more efficient and can charge faster than lead-acid battery chargers.

Also I believe that there are issues over self regulation of battery temperature during charge and discharge. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)

From what I have been reading on BMS it's even more complex as the BMS in a car seems to know the age of the battery and manages the charging according to the expected degradation with time. The following might no be the same as for the FL2 but the description implies that you shouldn't try messing about with different battery chemistry.

BMS on the Discovery Sport is quite advanced measuring both voltage and current (in and out) in order to calculate a State of Charge. Measuring voltage only is pretty unreliable to assess SoC.
The BMS module measures battery voltage and current which provides information about the battery state of charge (SOC) and state of health (SOH). SOH measurements provide an indication of battery condition. The BMS compares this information to new and used stored battery values.
Battery information is then communicated to the rear junction box (RJB) over a LIN bus connection. The RJB transmits the battery information to the instrument cluster via the MS CAN bus.
The instrument cluster displays battery charge warning messages to indicate generator or BMS faults. The instrument cluster also acts as a gateway between the MS CAN and HS CAN bus networks to transmit battery condition information to the ECM from other modules (audio and climate control, for example).
Based on the information received from the BMS module, the ECM will control the output from the generator via LIN bus. The ECM can also request the switching off or reducing of power to electrical loads if necessary and override the BMS signals if a fault is detected.
The BMS also monitors battery status with the engine switched off, sending a signal to switch off the infotainment system if necessary to protect the battery condition. Once triggered, the engine must be run for at least 5 minutes to charge the battery before the infotainment system will be allowed to operate with the engine switched off for a second time.
Periodically the BMS module will instigate a self-calibration routine. To self-calibrate, the BMS first charges the battery to its full condition. Once the battery is fully charged, the BMS will discharge the battery to approximately 75% of its full state of charge, but never lower than 12.2 V. The time taken to complete this part of the routine is dependent on the electrical load on the vehicle and the length of time the vehicle is used.
When the second part of the routine has been successfully completed, the BMS will return the battery to its optimum level of charge. The optimum level of charge will be between 12.6 V and 15 V, depending on battery condition, temperature and electrical loading. This process is run approximately twice a year. 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE

No wonder the garage's 5 second quick test, often disagrees with what the car has decided the state/charge of the battery is.

I do know, from experience, that following a really cold morning start the BMS tells the car to run in a lower (automatic) gear to assist the alternator recharge the battery.

It's the interconnectivity, of the various signals to the various modules, that can make faults difficult to trace. Changing out likely parts to cure the problem is, I am afraid, a dying art. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 76k+ miles) (MY2015)

IanMetro wrote:

Mr Google says
Lead acid battery chargers typically deliver a constant voltage charge, while lithium-ion battery chargers typically deliver a constant current and constant voltage charge. This means that lithium-ion battery chargers are more efficient and can charge faster than lead-acid battery chargers.