Advice on permanent alternator removal

Topic: Advice on permanent alternator removal (Read 2178 times) previous topic - next topic

Advice on permanent alternator removal

June 05, 2018, 06:43:40 pm

I would like to remove the alternator and lead engine batteries in favor of lithium batteries, solar and shore power. See photo of the current alternator belt system. I would like to get a slight bump in fuel economy and power. Should I either:

- Replace the alternator with a dummy pulley of the same size and belt
- Reduce the length of the belt

The lead acid engine batteries will be replaced with a 400AH lithium LiFePo4 battery pack, which will be charged with either shore or solar power. The advantages are:

1. Faster starting: High-current starting capacity: 4000Amps
2. Backup 12 Volt coach battery, deep cycle. If the house battery goes down, there is a high-capacity alternate supply.
3. Maintenance-free
4. Lighter than lead batteries
5. Should last 20 years
6. Better performance of house systems: Water pump, heater, solenoids due to higher voltage: Constant 13.2 volts (3.3v x 4)
7. Much lower self-discharge

The four lithium cells will be charged and balanced by an iCharger 4010 duo intelligent battery charger. Alternators cannot charge and balance lithium cells and do not have the following features:

1. Intelligent charge with full cell charging limit.
2. Storage charge. This charges to 50% SOC (State of Charge) and is good for long-term rig storage.
3. Test cell capacity (Amp Hours).
4. Bottom cell balancing and charging.
6. Charge on shore or solar power from the inverter.

Your advice is welcomed.

See photos.

Re: Advice on permanent alternator removal

Reply #1 – June 05, 2018, 07:09:23 pm

Your alternator uses just a few HP at max output.

There are four step alernator controls that work with every type of battery including Lithium. Look at the ProRegU specs
https://baymarinesupply.com/media/downloadable/Sterling/ProRegulator.pdf

Re: Advice on permanent alternator removal

Reply #2 – June 05, 2018, 07:17:16 pm

While I do NOT agree with taking the alternator out of the charging equation, were that my desire, I would leave the alternator in place and electrically disconnect it. Using it as an "idler" would would take close to zero HP and leave you with the option of reconnecting it if you change your mind.

Re: Advice on permanent alternator removal

Reply #3 – June 05, 2018, 07:36:07 pm

Approx 2.5 hp at full output. Redundancy is a key feature on these coaches, why eliminate one? Nuclear winter, zombie apocalypse, you might need it.

Re: Advice on permanent alternator removal

Reply #4 – June 05, 2018, 08:22:05 pm

Thanks for the advice. No alternators can safely charge lithium batteries because they do not know about lithium voltages and do not monitor all four cells. Plus, it shortens the life of lithium cells to keep them at 100% SOC when in storage. The ProRegU is only for lead batteries.

Guess it would be good to leave the alternator in place in case this experiment fails, or the next owner wants to change back to lead.

If we have an apocalypse, the solar system will still function after running out of diesel. The genny could also charge the engine battery with my proposed system.

Re: Advice on permanent alternator removal

Reply #5 – June 05, 2018, 08:25:47 pm

Drive at night without generator running, you will quickly learn how important the alternator was. Headlights, dash heater a/c fan running on high and engine all will drain your start batteries. Cannot always count on solar during the day.

Re: Advice on permanent alternator removal

Reply #6 – June 05, 2018, 08:28:29 pm

Please look more closely at the ProRegU. It clearly has settings for Lithium batteries. Call Alan at Bay Marine and ask him for more details or perhaps another suggestion.

Having no charging system other than solar, land line or generator seems like a disaster waiting to happen. DWMYH.

Re: Advice on permanent alternator removal

Reply #7 – June 05, 2018, 08:41:54 pm

Balmar MC-614 is another regulator that has adjustable settings. I've used that one on my Newell with 1000AH LiFePO4 system, house batteries only. I don't remember the settings but basically had to dial it down so the max voltage was compatible. Also you have to limit the amps so you don't damage the alternator.

Re: Advice on permanent alternator removal

Reply #8 – June 05, 2018, 09:20:25 pm

Repurpose the alternator into a regenerative braking device (easy) and be the coolest kid on the techno block

Re: Advice on permanent alternator removal

Reply #9 – June 05, 2018, 10:05:26 pm

Tim,

May I suggest 4/0 cable from battey positive to starter and 4/0 cable from battery negative to engine block. Big wire for big cranking amps. These cables may be on current starting batteries and can be repurposed. I had less than 4/0 on my coach and changed my cables to 4/0.

Hope this helps. All the best and much success on your project.

Re: Advice on permanent alternator removal

Reply #10 – June 05, 2018, 10:41:38 pm

Only issue I ran across is that li-ion batteries do not output power quickly.

My dirt engines would turn over slowly. Required turning on the headlight for a few minutes to build voltage up enough to start the motor.

Different chemistry. Not the most power output until used a bit.

Re: Advice on permanent alternator removal

Reply #11 – June 06, 2018, 01:10:25 am

While I am a BIG fan of LiFepo4 battery tech, and bought this coach precisely due to it having it, and solar, I would not take out the alternator EVER. The BMS system will keep the batteries from overcharging, and I would not EVER install a LiFepo4 bank without one. Witht the coast of lithium, not sure it makes sense to sub it out for lead acid for starting. If you really wanted to lose the weight of the lead, and really on a coach this size, whats the difference.... Get some capacitors for starting and have the boost set up to pair it with your house bank if needed. You will need the power when driving down the road. And there will be times when solar isn't there.
But if you really want lithium for starting battery, keep the alternator and set the bms up so they don't overcharge.
Bob

Re: Advice on permanent alternator removal

Reply #12 – June 06, 2018, 09:15:58 am

Leave the alternator. Get a smart or adjustable regulator. Common in marine applications.

Another option is to have a manual disconnect switch (Perko ON-OFF switch) between battery isolator and house bank that isolates the house batteries while driving. Probably the simplest solution. Could be installed at base of bed where it could be easily accessed.

Re: Advice on permanent alternator removal

Reply #13 – June 06, 2018, 04:12:32 pm

Thanks for your feedback and making me think before I leap. I used to be a mediocre power supply design engineer, so forgive my nit-picking. Two major points, A and B below:

A. No practical smart chargers for lithium
There are no all-in-one lithium alternator regulators on the market that meet my requirements. I researched many regulators, including the Smart Charge R210A and Balmar MC-614. None pass requirements needed to safely charge and store LiFePo4 batteries for the following reasons:

The R210A and the Balmar MC-614 are admirable voltage regulators for lead-acid batteries. However, they appears to be a jury-rig for LFP batteries because they regulate voltage, not current. LiFePo4 batteries will draw excessive current at a constant voltage. They do not have three crucial features:

SHORTCOMINGS OF SO-CALLED "SMART' LITHIUM REGULATORS
1. No Current Detection
A constant current charge is required. A current shunt and a current adjustment is required. Regulating current by sensing the temperature of the alternator, then throttling field current based on temperature could cause an over-current condition when the alternator is cold. I would design the system with a Hall-Effect current sensor to replace the old fashioned shunt. Here is an excerpt of the PDF of the LFP algorithms:

9. LFP Constant Volatage 14.5 volts 30min then 13.4 volt rest voltage. C.V. time 20min.
0. LFP Constant Strait 13.4 volt cruiser voltage.

Both of these have constant voltage. They should have contsant current algorithms.

2. Over-voltage limit at the individual cell level
Sensing the voltage of all four cells is a "must have" because one cell will go over-voltage before the rest, thereby damaging the cell.

3. Cannot limit SOC
When the rig is shut down and put in storage, the SOC must be between 50% and 80% to maximize longevity of these expensive cells. This should be user-selectable.

See https://www.bruceschwab.com/wp-content/uploads/sites/86/2014/02/170928-Smart-Charge-R210a.pdf

The regulator companies need to hire competent engineers skilled in lithium chemistry, safety, sustainability and longevity. No offense is intended. These companies are hanging on to 200 year-old lead-acid technology, which is primarily charges using voltage sensing. An alternator regulator with a built-in current detection and BMS is needed.

I ran into this mentality with an engineer at Morningstar, the solar charger company. They refuse to see that lithium batteries can be damaged using lead-acid algorithms. My lithium batteries were damaged by a Morningstar controller because it could not detect over-voltage in several of my 16 cells. Cost me $400 to replace the bulging cells.

B. NEED TO CHARGE WHILE DRIVING
I agree with commenters that eliminating the alternator may cause unforeseen issues. Worst case watt-hour analysis of engine battery power requirements (watt hours) and rough KWH estimate include:

- Drive for 14 hours at night
- All lights on (30A x 14hr x 12v=5.04KWH) (Time to get LED headlights!)
- All accessories on (blower, radio, AC) (10A x 14hr x 12v=1.68KWH)
Total=6.72KWH This is a 1.9KWH deficit.

Although I do not have certainty about the above power calculation, the loads could likely exceed the 400AH, or 4.8KWH battery capacity. But since the engine battery will now be charged with the inverter using the 48Volt 9.4KWH house battery or the generator while en route if required. I do not see an issue, especially if LED lights are installed.

PS: I like the comment about regenerative braking. Ha ha. How about a wind generator?

Re: Advice on permanent alternator removal

Reply #14 – June 06, 2018, 04:21:52 pm

Quote from: Tim – June 06, 2018, 04:12:32 pm

How about a wind generator?

Suspect this was posted as a joke-- wind resistance while driving would well exceed power output.

Said another way no device, and particularly a wind generator is close to 100% efficient.

Re: Advice on permanent alternator removal

Reply #15 – June 06, 2018, 05:20:54 pm

So If I read this correctly, you pretty much made up your mind to do this before you asked the question. Fair enough. You are going to an all Lithium battery setup with no alternator where all of the lithium batteries can only be charged by land line or solar. (I asume you can use a generator to drive some acceptable charger to charge the batteries.)

I find it very hard to accept that there is absolutely no alternator charging solution for Lithium batteries. Maybe what you should do is replace the alternator with an engine driven 120v generator that can drive your acceptable 120v charger.

Have you ever considered that your system as you designed it is leading you down paths for which there are no solutions (acceptable to you) to the problems you create? Sort of like painting yourself into a corner.

Re: Advice on permanent alternator removal

Reply #16 – June 06, 2018, 11:28:45 pm

Good idea about the 120 VAC alternator. Thanks! I will investigate it.

I want to do this project because:

1. Bought the 400AH lithium batteries at 70% discount. Long story.
2. In my reirement, I am a solution looking for a problem, even if there was no problem in the first place.
3. Would like to be a leader in new battery and green technology.
4. Would like to debunk most of the quackery about lithium battery maintenance and sustainability on the Internet.
5. Companies are making a killing off of inexperienced lithium battery customers and I would like to assist these buyers, sort of like Ralph Nader.

Re: Advice on permanent alternator removal

Reply #17 – June 07, 2018, 06:22:35 am

We have run our lithium system for about 18 months now. We currently have 1180 on top and 400A of storage. I did not want two different battery types using a common charger although Victrons Cyrix is available. I chose to isolate the two battery banks by using a simple marine switch. I have also set up the genset to fire off of either bank. Standard is chassis.

I have yet to have any charging issues requiring using the alternator to charge our house bank but in an emergency it is available. The rapid recovery, no absorption phase, lithium provides probably is part of the equation.

I also created a much more capable boost circuit if needed. I don't know your system nor am I an engineer but there may be a more simple system that allows you to keep the alternator and still meet most of your objectives. Good luck!

Re: Advice on permanent alternator removal

Reply #18 – June 07, 2018, 08:48:37 am

Do your lithium batteries have a built-in BMS?

Mine do not, so I plan on using an advanced RC charger, the iCharger 4010, to act as a BMS. It has many cool functions:

- Charging at selectable current and voltage settings
- Balancing cells, bottom or top method
- Storage charge, to maximize longevity. This is a must-have feature, since storing lithium batteries at 100% SOC can shorten their life.

See iCharger 4010Duo - ProgressiveRC

Re: Advice on permanent alternator removal

Reply #19 – June 07, 2018, 08:52:46 am

Bob (post #11 above) just bought a coach with Lithium battery "conversion".

Might get together with him and perhaps the previous owner who designed and installed the system.

Re: Advice on permanent alternator removal

Reply #20 – June 07, 2018, 09:52:46 am

I have a racer bud that is my EE go to guy. He is the lead engineer on a few electric race vehicles. I will put him onto this thread and see if he may be interested in assisting.

Re: Advice on permanent alternator removal

Reply #21 – June 08, 2018, 06:50:40 pm

I asked Alan Ferber at Bay Marine Supply if it is possible to charge Lithium batteries with the alternator.

Here is what he said ...
"It is definitely possible to charge a lithium [with] a regulated alternator, you just set the voltages appropriately and cut the absorption period to a minimum. The problem with smart regulators is that newer cars need to set their own voltages, otherwise the vehicle's computer thinks there's an error. That's where Sterling's alt-to-battery and battery-to-battery chargers come in, since they leave the vehicle's voltages alone. On boats, with diesels and no engine control module, we use smart regulators.

In the end, lithium does fine on an AGM profile. Just set the absorption period short. And if it's a vehicle that's not running 24 hr a day, it's even less of an issue."

The solutions available to complex problems usually start with an open mind.

Re: Advice on permanent alternator removal

Reply #22 – June 08, 2018, 07:18:25 pm

Quote from: Roger & Susan in Home2 – June 08, 2018, 06:50:40 pm

In the end, lithium does fine on an AGM profile. Just set the absorption period short.

SO, from a practical/cost effective standpoint, if one uses two things will this work:

Smart regulator-- been available for decades for the marine industry.

If the smart regulator does not allow for a time-limiting factor: Mechanical ON-OFF switch to shut off charging to the LI batteries after XX hours of charging/driving.

Re: Advice on permanent alternator removal

Reply #23 – June 08, 2018, 08:34:49 pm

Brett, I think that is right. Not every system is going to be completely automatic. In the end they all need the attention of a conscientious user whose goal is continuous learning. This is an evolving battery technology in a mobile installation in a wide range of temperatures. I think it is simply going to continue to improve. I am looking forward to what comes.

Re: Advice on permanent alternator removal

Reply #24 – June 08, 2018, 08:36:43 pm

Technomadia has an interesting read on this subject, when they converted their batteries, not for sure if they are the same type.

http://www.technomadia.com/lithium/

Affiliate Notice