Arco Zeus Alternator Regulator Bench Test

[Starrider]

I am starting this thread with the hope to help us owners make more informed decisions when upgrading our boats to a lithium battery bank. A lot has changed in the past year that make upgrading to LiFePO4 easier and yet most boat forums continue to offer “stale” recommendations. I will document each upgrade as it occurs to our sailboat

Every boat is different and each person wants something a little different, but this is what we wanted our upgrade to entail.

1. Batteries. We wanted to use (3) 24 case size LiFePO4 batteries that fit in the exact space that the present AGM batteries are in. Did not want lengthy high current wires and batteries running everywhere as we have a 3,000 watt inverter/ 150 amp charger. We wanted batteries that have a Bluetooth connection so we can see the exact state of charge, voltage, cell balance and temperature, amp hours used, current to and from the battery, time to discharge and time left to recharge. We also wanted batteries that the output can be turned off with an app. We wanted batteries with internal heat so they can be charged and discharged in cold weather. We also wanted batteries that will protect themselves from overcharge by turning off the charging circuit in the BMS and not turning off the output of the battery. And like all LiFePO4 batteries, they will shut down output on over current and over temp.

Many LiFePO4 batteries still sold today shut the entire battery off on overcharge voltage or cell imbalance, thus destroying your alternator and leaving you without power. I tested this on the batteries I purchased and they will indeed still output power but shut the charge mos off in the BMS on over voltage. The app clearly explains what is going on in the battery and gives error codes. We purchased 5 of these and 2 of them have been in use for a month in series (24 Volt) on our M151A2 Military Jeep. Batteries in series tend to become unbalanced and these are staying balanced due to an excellent BMS and good cell quality. The best quality LiFePO4 cells available are called EVE cells and those are the cells used in these batteries. Because of this, these batteries have an 11 year warranty.

These batteries are sold and supported here in Georgia USA. Anytime I had questions, they answered the phone. Try that with a battery purchased from Amazon! A five year battery warranty from an Amazon seller will most likely not be around if 5 years, they come and go all the time. Look for battery teardowns on you tube, there are some really shitty batteries on the market. You get what you pay for and we do not want to be 100 Miles off shore with a cheap set of batteries!

Oh yea, did not want to spend $1,000 a piece for batteries that have no Bluetooth. We purchased these on sale end of last year for $340 each, not bad for a premium battery with marine and UL approvals (important for insurance and safety reasons).

These are the batteries we purchased. https://www.epochbatteries.com/produ...och-essentials I have no financial interest in this company, research shows good reviews and battery teardowns show excellent quality.

2. Alternator Charging. Yes, folks are still recommending keeping an outdated expensive, heavy AGM battery on board as your start battery. Then to make it worse you have to add a DC to DC converter to that start battery and add more wiring, switches, fuses etc. to charge your new LiFePO4 batteries. Oh, the DC to DC charger now limits your alternator charging to 30 amps unless you want to add 2 of them (more expense and wiring). Short of spending over $1,100 for a Balmar alternator and regulator, these were the only ways to deal with it. Almost forgot, the Balmar will not directly fit and new brackets and spacers have to be machined, more $ and aggravation. And the balmar does not have any way to limit charge amperage or charge current vs engine rpm.

Folks, there is an easier way. Purchased this Alternator regulator. https://arcomarine.com/products/arco...ator-regulator Expensive but found a dealer that sells it for $225.00 cheaper.
This will allow you to use your current alternator (with a simple modification) to charge your new LiFePO4 batteries.
Throw away the AGM battery, DC to DC converter and wiring and use KISS (Keep It Simple Stupid). New LiFePO4 batteries now have the current to start our tiny engine. Leave the battery switch to the all position and you have hundreds of cranking amps available to start your Westerbeke. My tests and manufacturer battery spec sheets show only one battery will start our engine but keeping the battery switch to all 3 will prolong the life of the batteries and BMS.

I was so ecstatic about this regulator simplifying a LiFePO4 battery upgrade, created a video today putting it through it’s paces on my test bench. I have no connection or stock in this company, lol, just a great product to share with all of you. No other regulator on the market can do this and everything, and I mean everything is programmable with an app. Here is the video https://youtu.be/v-b5Dp2JcHk?feature=shared If anyone is interested on how to modify the stock alternator, I can create a video of it. However any alternator shop can add a field wire to it as well.

Unfortunately, all of the equipment we installed in Starrider in 2007 does not have Lithium profiles. So we need to upgrade our solar charge controller and monitor and the Battery amp hour meter. We will be using Victron products as they can create a Bluetooth network and the battery amp hour meter can share battery state of charge with the solar controller so the batteries are never overcharged or undercharged. Will document this in the spring when the weather is more conducive to working outside.

Hope this helps someone.

[Ixium]

Yeah, every where you look the experts are saying to always have an AGM and then put a 30amp dc2dc charger to charge your lithiums. Then what was the point of the experts saying a while ago to get high out out alternators? Well you can daisy chain the dc2dc chargers… just more wires and more boxes.

Even at a big boat show that I was ask, all the “experts” said you need a dc2dc.

My boat came with a 120amp balmar alt and external regulator. My plan is to just under power the charging profile so at max the alternator can get the batteries is 80%. No risk of a high voltage cut off. It already has a high temp cutoff so less risk of frying the alternator.

[The Yacht Rigger]

Originally Posted by Ixium

Yeah, every where you look the experts are saying to always have an AGM and then put a 30amp dc2dc charger to charge your lithiums. Then what was the point of the experts saying a while ago to get high out out alternators? Well you can daisy chain the dc2dc chargers… just more wires and more boxes.

Even at a big boat show that I was ask, all the “experts” said you need a dc2dc.

My boat came with a 120amp balmar alt and external regulator. My plan is to just under power the charging profile so at max the alternator can get the batteries is 80%. No risk of a high voltage cut off. It already has a high temp cutoff so less risk of frying the alternator.

You only need DC-DC when you are charging with a "dumb" alternator. With an externally regulated alternator and a regulator like a Zeus you can charge the lithium bank directly at extremely fast rates, and safely. Not sure who you spoke to at the boat show, but this tech definitely works.
We just made a basic instructional video concerning the Zeus wiring here:

https://www.youtube.com/watch?v=zDbQ_ILbeA4