I wanted to see if anyone has replaced their conventional, lead acid battery with a Lithium Ion equivalent. I have the XS Power D4900. First, is this even possible? Would love to hear the process and implications of switching.

https://www.summitracing.com/parts/xsp-xv4900/make/jaguar/model/xj/year/2012

 

jschimmels, I see 2 issues that would need to be dealt wtih. The first and more concerning is that the terminals that are in the car's wiring harness do not match up to what this battery has. So, you have to modify the car's wiring harness to make this work or fine adapters that screw into the battery to adapt the post to what the car needs.

The second issue I see is the low CCA rating. the battery you post only has 670 CCAs, the AGM battery is over 800 (if not pushing 900). You have a fairly good size motor in the car and it will need that power to crank over the engine. So, this would probably be a "good battery if where you live never drops below say 50F.

I see a potential 3rd issue, but there is not enough info to say positively it is an issue. The AGM battery for our cars has an 80 amphour rating. So, this would mean that if you do a little bit of math, it would have around 1000 watts of stored energy in it. The rating for this battery is only 70 (no, not 700). So, this would indicate to me that it may not have a lot of reserve power for bad times. What I mean by this is if you are say having a problem getting the car to start, an AGM battery may let you crank the car for say 5 minutes, this battery will give you maybe 1. Also, the large capacity of the battery means it can take larger surges and smooth them out. This is critical for modern day electronics. This is why we talk about having an old battery and getting random error codes. That battery may only have 50% of it capacity (500 watts) and it starts giving you issues because the voltage is moving around too much. What you think is going to happen with a capacity of only 70 watts?

Maybe I am wrong. I am just basing it on years of experience with much larger batteries and a lot of learning from other members here and their issues with batteries that were either old or not sufficiently sized. Gotta love working on a battery that can power a small town (or a nuclear submarine) for a few hours.

 

Why would you spend $500 for a Lithium ion battery when you can buy an AGM battery for less than $200? IMHO, you are wasting money and looking for big trouble, as Jaguar electronics probably aren't compatible with a Li-ion battery. Why risk overheating a Li-on battery and frying your alternator and wiring? Just because it can be done, doesn't mean that it makes sense to do so for a street car like your XJ.
Replacing AGM battery with Lithium-ion battery

P.S. It's been done by @jahummer in the X150 Forums for his race car, a heavily modified 2008 XKR. He saved 53 lbs.
https://www.jaguarforums.com/forum/x...uccess-247840/

 

First off, why would you even want to do this on a street car? A proper lithium equivalent will be about 6X the cost of an AGM. There are numerous benefits to LiFePO4 versus AGM but also some downsides.
You can't compare like for like specs between AGM and Lithium, they're completely different.

https://antigravitybatteries.com/pro...tive/ag-h8-rs/

 

Been used LiFePo4 batterys for weight saving and safety in racing applications +10 years, but no real benefit for street car.
Note: LiFePo type of cells don´t have same voltage/charge level curve than conventional batterys, so your vehicle BMS system might not charge it full (or at all)
Li-Ion battery: No. Just No. (unless you want to burn you car)

 

 

The LiON battery isn't much more than the lead acid. I currently have the D4900 and it lasted 3 years. Does the LiON battery last longer? Other answers have convinced me this isn't the route.

 

Equivalent amp-hour (Ah) in Lithium batteries is quite a bit more, the cheapest 100Ah lithium battery I could find here with a ten-second google search was almost $1000 vs $389 for an AGM on the same size. Lithium in the same capacity is about half the weight of AGM, and when someone says they've saved LOADS of weight with lithium they've usually gone from something like 100Ah to 30Ah. Indeed the "Anti-gravity" brand makes batteries with about a third of the capacity of what they're replacing, and sells them for thousands to people who don't read or understand the specs and then wonder why their car doesn't run properly.

Lower-capacity lithium batteries are the ducks nuts in race applications where you need just enough power to start the car, but very little power to run the thing once it's going. For street applications ensure that the "Ah" rating of the new battery matches or exceeds the old battery.

 

A deep cycle battery’s not suitable for automotive use, ever.

AGM batteries last about 5-6 years, some longer. LiFePO4 should last longer than that, but again at 6 times the price of an AGM equivalent. So why do that?


EDIT: deep cycle’s for continuous use in devices which operate on DC voltage. AGM or flooded batteries are built for short but substantial current draws such as starting combustion engines,

 

Great thoughts - I will stick with the standard battery.