Lithium Battery Upgrade

As our 2 six volt flooded lead acid batteries near the end of their useful life I am contemplating replacing them with two 100 ah Lithium batteries.  Our existing lead/acid ones are OEM installed and are approaching 5 years old.


For those PC owners that have purchased the Lithium battery option or retrofitted with Lithium one of my main questions centers around the engine alternator charge system.  The basic Phoenix system uses a solenoid to allow charging of the coach batteries while the engine is running.  Because the Lithium units have much lower internal resistance than the lead/acid units I would anticipate significantly higher amperage (charge rate).  I am concerned this may overload the Ford alternator and cause early failure.


I see on the internet some recommend a DC to DC charger to regulate current flow and thus not overload the alternator.  I am curious if Phoenix Lithium installations include anything to regulate this current flow or if the basic PC installed alternator charging system is adequate?


I have a Progressive Dynamics PD9270 converter that I will have to determine if it is suitable.  The same goes for the Morningstar solar controller.


I anticipate with all the crowded National Park and National Forest campgrounds I will be looking to do more boondocking thus my current interest in Lithium.  I know the use of the generator will adequately provide power but because of noise I prefer not to run it.


Any thoughts or experiences with Lithium batteries would be much appreciated.

fandj,

Given you have 6V batteries that lasted 5 years is a testimony that two-6V in series is better than two-12V in parallel.

I had researched lithium technology and decided against it for many of the same concerns you mentioned.  I went with 6V AGM batteries which was a good compromise, and affordable too, about twice that of lead acid equivalents.  In my case I needed maintenance-free due to ditching the battery tray to get the height needed for taller 6V batteries.  Our battery compartment with tray was designed for 12V batteries which are a few inches shorter.

FWIW: I installed our AGM-6V batteries back in 2015 and they are still healthy though it has been a few years since we worked them hard.  Our trip this year will reveal much.

I am still doing my research on converting from 6 volt lead/acid batteries to 12 volt Lithium.  To possibly help present and potentially future Phoenix owners that are evaluating their battery options here is what I have gleaned to date.  Discussion with Progressive Dynamics revealed my PD9270 converter while designed for lead/acid batteries it would provide acceptable performance when used for Lithium.  To make sure it provides adequate charge voltage one would tap the Charge Wizard to boost mode which supplies 14.4 volts for 4 hours which should bring the batteries at or near 100% full charge.  At that point the controller would cut charging to about 13.6 volts.


As to the question to what is required to manage Lithium charging while driving it appears with the low internal battery resistance it would be possible to overload and damage the alternator.  The Phoenix supplied charge wire from the alternator/battery would be too small to properly manage the charging of the house Lithium units.  It appears the recommendation is to use a dc to dc charger which would limit current. The existing small charge wire from the battery/alternator would be replaced with a 6 awg wire. With the current Ford alternator it appears the consensus is 30 amps charge current is a good target which would allow for fairly rapid recharge and not damage the alternator.


I still would be interested in anyone with the factory supplied Lithium option what engine to house battery charge system is used.  There is a lot of info on the internet and some of it is contradictory.  It would be great to hear from a fellow PC owner that has first hand experience.


Fred

My brothers in the process of making this conversion on his travel trailer. He is installing a DC to DC charger in the truck to properly charge the batteries While driving. In addition, he has a complete battery management system. The system connects to and monitors each of the cells that makes up the batteries. He is a total of eight cells. The management system is a lot more sophisticated than a standard charger. I can inquire more about his system if it would help.

PS he also confirmed with my son, who works for Ford, that the F150 alternator has enough output to charge those batteries. Maybe worth verifying that the E4 50 alternator has that capacity

If you need a higher output alternator, one was available (2007 model year) as follows.  I got it from Ford document Bulletin Q-150 dated late 2006.  Later chassis model years might have this higher-output alternator by default.  I cannot rule out the possibility that even I have this alternator in my own 2007 E350 chassis.

A new 135 Amp alternator kit (service part#: 7C2Z-10344-A) is now available for purchase through your
local Ford dealers. This alternator kit provides greater output at idle and at peak. Refer to Technical
Service Bulletin (TSB) 06-25-11 when talking to your local Ford dealer.

If such an upgrade is still inadequate, consider Ford's emergency vehicle alternator package.  BUT....it gets complicated involving reprograming the BCM and such.  Do a Google search on this "QVM Bulletin: Q-160" and you will get lots of detail.  Ford installs either a second alternator, or a higher-yet output single alternator.

As for me, I would not consider a drastic change.  The 1st choice (135 Amp) seems harmless enough.  I like to keep things "simple & common" so that if a break-down occurred in a remote area, I can get the parts and service in good time.  I share this only for PC owners who are desperate for more alternator output.

When I initially read this thread I thought  the concern was that the charging current from the alternator might be too high? Perhaps the OP should ask Battle Born.  This is from their website:

“We recommend a 50 amp charge rate for a 100 Ah battery. You can charge at a higher charge rate of 100 amps in emergency situations where it is necessary, but we don’t recommend it for long periods of time”.

I have consulted with Battleborn support and they recommended for two of their 100 amp hr batteries a 30 amp dc to dc charger be used.  My take of the phone conversation is the 2 batteries could accept a charge current of 100 amps, the 30 amp charger would be a reasonable balance of not overloading/overheating the alternator,  a fairly fast recharge rate, a reasonable recharge cable size (6 awg), and a significantly less expensive charger than a 100 amp charger.  For example if the batteries were discharged by 50% (100 amp hr) a recharge could happen in about 4 hours of driving which would be reasonable for our style camping.  This is significantly faster than what is possible from my PC lead/acid system.  Obviously one could use solar, generator, shore power or any combination to recharge the battery bank but being able to recharge from the engine alternator while driving in this short a time would be nice.


I found the Battleborn support person very helpful and willing to take whatever time was necessary to answer my questions.  I would recommend anyone considering a Lithium upgrade contact Battleborn or other battery supplier for their input for their specific product.


Fred

Just found this link related to differences in charging requirements for SLA and Lithium batteries.  Hopefully it would be useful for anyone considering a change to Lithium.


https://www.power-sonic.com/wp-content/uploads/2019/04/How-to-charge-LiFePO4-batteries.pdf

Update on installing my Lithium system:

I needed to replace my AGM batteries when it became noticeable they were not holding a charge.  After review of the literature and speaking with other RV owners I elected to go with the Battleborn Lithium batteries.   

In addition to the Lithium batteries I replaced by Parallax 5300 converter with a Progressive Dynamic PD 9100 L specific for charging Lithium batteries.  In order to swap out the Parallax converter I did have to install an outlet.  The Parallax converter was hard wired the Progressive Dynamic is a plug in. 

I also swapped out my Midnight Kidd solar controller for a Victron 100/50.  I anticipate in the near future of adding another solar panel, which is why I did not choose the 30 amps.

Several months ago I added the Victron BMS 712.  This has been very helpful providing information on my previously installed AGM.   Battleborn did walk me through the new settings when I added the Lithium batteries.

The question I was unsure of:

Does one need a dc-to-dc charger?    I was able to talk with Ed,the electrician at Phoenix Cruiser.  He felt that it was not necessary to add a dc to dc charger and that the present wiring to the solenoid along with the heavy duty alternator they install was sufficient to provide enough amps to the Lithium batteries to keep them fully charged.  Ed has met with the Battleborn representatives asking many questions to include the dc-dc charger.

So for now, despite having ordered the Victron Orion dc-dc charger, I will hold off installing it.   We have a trip planned for the midwest coming up in a couple of weeks.  I do have an appointment at the factor for some other work.  When I am there I plan to talk with Ed again providing him an update how well the present system charges the Lithium batteries from the alternator.

Any thought?  It still makes sense to me to install a dc to dc charger especially the Victron which provides a 3 stage charge to the house batteries.  But for now will hold off.

dave
2017 -2910D

Dave,
Thanks for the info on the PC chassis to coach battery charging system.  You have a good setup with the Victron 712 BMS to determine charging current to your Lithium batteries.  I would be curious when you talk with Ed to learn if Phoenix made any changes to the solenoid, wire, fuse, etc. when they install the Lithium option.  I am not sure but it looks like the charge wire in our 2016 is either a 10 or 12 gauge  which has a 30 or 20 amp ampacity rating respectively.


I don’t have voltage/current curves for the Lithium battery but with a alternator output of 14.4 volts it may very well be self regulating without exceeding the ampacity of the wire.  If that is true one could indeed expect some reasonable charge without overloading the alternator.  Probably would not perform as well as the dc to dc charger but not requiring any modification certainly would be simpler and less expensive.


Fred

On my 2015 (built on a 2014 Chassis) the Ford alternator shows as 120amp from the factory... Plenty of output.  However, the self-resetting circuit breaker from the alternator to the underhood solenoid is a 40amp breaker.

Donc13 - Are you running a lithium battery system and charger with that alternator?

Donc13 - Are you running a lithium battery system and charger with that alternator?

No, I have Lifeline AGM batteries.   No issues with them.  220 amp hours, serve my needs very well.

Was just noting that from the factory... You can only get up to 40 amps via the alternator to charge/run the house 12v batteries.   If someone wants to charge the house batteries with more current, they are going to have to rewire or add another feed from engine battery to charger, and have it isolated so when the engine is off, no 12v goes from the engine battery to the "house".

Don