Replace 12V lead battery with lithium-ion

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jenjc

Member
Joined
Sep 10, 2014
Messages
23
Hello everyone,

I have a 2014 FFE and we're getting a little tired of replacing the 12V lead battery every three or so years. Has anyone put in a lithium-ion battery instead? My electrical engineer husband doesn't see why we shouldn't because:
  • You don't need power to "crank" the engine
  • They have safeguards now to keep lithium batteries from draining or getting too hot
  • There is greater capacity in the lithium-ion battery

The wisdom of anyone's experience would be appreciated. Thanks!

Jenny
 
I've been running an Ohmmu 12V Lithium battery since March of last year and had no issues (Previously had it in my 2012 FFE, and now use it in my 2017), other than fitment the first time (Terminals sit higher, but it will fit in the same space as the lead acid battey). At the time I bought the battery, they didn't have an option for the FFE, so I went with a standard one (no bluetooth, and no self-heating tech ) meant for the Nissan Leaf at $379. Weighs just 11 pounds, so that's 19 pounds of weight saved over the lead acid battery. I've also used it for powering small appliances like a house vacuum via a 1000 Watt inverter. It's neat seeing the power Watt meter in the FFEs dash cluster registering the load.
https://www.ohmmu.com/product-page/12v-lithium-battery-for-nissan-leaf

 
jenjc said:
Hello everyone,

I have a 2014 FFE and we're getting a little tired of replacing the 12V lead battery every three or so years. Has anyone put in a lithium-ion battery instead? My electrical engineer husband doesn't see why we shouldn't because:
  • You don't need power to "crank" the engine
  • They have safeguards now to keep lithium batteries from draining or getting too hot
  • There is greater capacity in the lithium-ion battery

The wisdom of anyone's experience would be appreciated. Thanks!

Jenny

I would be very hesitant to do that. One issue you didn't mention is that the lithium can't charged in freezing temps. Also, because there's not much of a source apart from China, I would be concerned about quality control for an automotive application. Odyssey does make a 26R AGM pack that might be suitable. Are you keeping the car on while idling? That should reduce 12V drain and extend the life of the battery. I've only replaced mine once since I got the car, but my vehicle is a 2017 and it was the original battery. Swapping seems like a lot of cost very little reward. Changing the battery takes under 1 hour...every three years.
 
I got a fantastic price ($40) for an InduraPower LiFePO off ebay. Seems the company was going out of business and liquidating assets.
That battery needed some terminals and cables to hook up to the existing FFE battery cables. After that was done it worked with the car flawlessly.

However, one of the selling points of this battery was its Bluetooth connectivity, configurability, and control through the app. That aspect of the battery was not ideal. Yes, its cool to see the current draw and voltage of the battery on the phone, yes it is cool to be able to turn down the supplied current so that only clock and radio memory is saved, and the car cannot be started. Definitely a theft deterrent. Yes its nice that there is an advanced BMS in the battery and a heater and other features, and that it is supposedly made in Mesa, Arizona. But, when you look at the app, and it shows that you are losing 5% battery capacity every day the vehicle sits unused, you get concerned. The battery seemed to behave fine, but the software was misleading.

I felt uneasy leaving the battery in the FFE and moved it to my chevy metro. Well, waddaya know, the software is happy with that. The metro sat for 2 weeks in stupid hot conditions, and the app showed the battery lost only 1% the entire time. What gives?

And yes, I have set the battery out on the floor overnight and have seen it lose the 5% over a 24 hour period. While at the same time, showed that it was being charged out of thin air. So its not the FFE causing the problem. But maybe the fact that the FFE does not have a high current draw (starting), and the software in the battery needs to see this current draw. Dunno.
 
I ran a LFP 12V battery in my FFE for about 2 years prior to selling it. It had a 50A max current draw BMS and a 10V LV cutoff. It worked great. I wonder how long that battery would have lasted had I kept my FFE. It had no problems with winter usage either.
 
jenjc said:
Hello everyone,

I have a 2014 FFE and we're getting a little tired of replacing the 12V lead battery every three or so years. Has anyone put in a lithium-ion battery instead? My electrical engineer husband doesn't see why we shouldn't because:
  • You don't need power to "crank" the engine
  • They have safeguards now to keep lithium batteries from draining or getting too hot
  • There is greater capacity in the lithium-ion battery

The wisdom of anyone's experience would be appreciated. Thanks!

Jenny

I'm curious about your use of the car. It seems that with regular use, and a reasonable amount of attention, a lead-acid battery should last much longer. Occasionally I put a trickle charger on mine, if I'm not driving much, but it never needs to run for very long. I'm thinking that we're susceptible to adopting a view that a low maintenance vehicle is practically a no-maintenance vehicle, something which doesn't yet exist, and which is actually a dangerous view to hold. As far as a Lithium replacement, I guess my question would be: why add complexity (another BMS) and additional cost, if you don't need to?

As an anecdote, when I was in my 20s I drove a '62 beetle. I put in a new 6 volt Sears battery with a 6 month warranty, and it gave me over 10 years of reliable service. I can't recall ever needing to put it on a charger.

Thanks for your post.
 
Automotive Lead Acid batteries have been designed with regular high current demand in mind - spike of draw to turn the motor over and an immediate charge back up. It has implications for the lead peroxide build up and breakdown. Ours simply don't do that.

I drive mine every day and keep it on L2 charging whenever it's home - and my battery charge droops after the first year. Add in summer heat and it drops enough to throw faults. Trickle charging has, for me, only addressed the droop for that single day. The behavior has persisted across 3 batteries so far.

These issues aren't unique to the Focus, other full electric vehicles see the same issue.
 
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