Tuesday, March 28, 2023

Switching to Lithium ( LiFePo4 ) batteries.

Finally - Switching to LiFePo4 Batteries.

Our Flooded Lead Acid Batteries capacity has dropped enough to demand replacement. As all of the Battery Charging devices on Eximius have a Lithium Profile, now is the time to switch up.

    Battery Chemistry: I have spent months researching the Lithium options and the most important is the battery chemistry. Right now, the safest battery chemistry is LiFePo4 - Lithium Iron Phosphate. 
Battery Build: There are 3 formats available.
        DIY Build from LiFePo4 3.2v Cells
        Drop in batteries with built in BMS ( Battery Management System)
        Drop in batteries with external BMS ( basically - Victron LiFePo4 Batteries )

Battery Choice:
The DIY build is clearly the lowest cost, and the highest density ( Ah per given area ) but I'm not prepared to make such a big investment in time to make my own battery system. I want to go sailing.

Victron batteries are awesome, but not in the budget, but if they were, then that would be my choice.

Drop in Batteries with Built In BMs - lots on the market, readily available and very reasonably priced. Many of the brands have been tested to destruction by reputable YouTubers. 

My Choice: Chin Batteries, not only do they get good reviews, are available but I know other boaters that are using them successfully.

Battery Bank Size

I want to use the existing battery bank box. It's under the cabin seat just forward of the galley and is near to the distribution bus bar and the shunt, very little wiring to change.

I could fit a single 200Ah LiFePo4 battery with room to spare or 3 x 100Ah batteries, again with room to spare, but not room for 4 x 100Ah which would be great but just not enough room

 So, 3 x 100Ah Chin LiFePo4 Smart Batteries with built in BMS and Blue Tooth connection to monitor the battery internals.

Here's the Wiring Schematic:

Here's the Wiring Diagram:

Parts ordered, they should all arrive in the next 3 weeks. That will be after the St. Pat's weekend, a welcome break.

The plan:

  1. Drill the hole for the Battery Disconnect Switch
  2. Drill the holes for the Battery Bus Bars 
  3. Disconnect the Lead Acid Batteries and remove them from the boat
  4. Install the BusBars and the Disconnect switch
  5. Install the wires to the BusBars and Disconnect switch and to the Shunt
  6. Install the new Batteries
  7. Make up the wires from the BusBars to the Batteries
  8. Test the system
Tools: Cordless Drill and Hole Saw, Drill set, Socket Set, Digital AVO meter, Heat Gun, Crimper kit, Big wire cutter, Screw Driver and Screw Driver bits

  • Battery Disconnect Switch
  • BusBar
  • Fused Busbar
  • 12v LiFePo4 Batteries x 3
  • 1/0 Red Tinned Copper Marine wire 
  • 1/0 Black Tinned Copper Marine Wire 
  • Nuts & Bolts to hold the Busbar and Fused Bar in place
  • Heat Shrink tubing 
  • 3/16" and 3/8" Tinned copper terminals
Notes. I have ordered one of the three LiFePo4 batteries. I could install that battery but the others should arrive soon.

Everything has been ordered, and the bits are arriving. 

My schedule is pretty full for the next 12 days, so I should get everything by then and can complete the install by the end of the month. 

But it is a Boat!

Update: Tuesday March 28th.
All of the parts arrived except for the 4 Stud Busbar, they should be here in a few days. Meanwhile, the 3 Chins LiFePo4 100Ah 12v batteries arrived and have to be charged to 100% I'm really glad that I went with the Blue Tooth Option, it's really the only way to know what's happening inside the battery box.

I purchased this charger online from Amazon.
It's a 4amp LiFePo4 charger.

The charge status is shown via 4 Green LEDs.

When charging, the LEDs flash in sequence from the bottom to the top.

As the charge progresses, the lowest LED will stop flashing and show solid, that's showing 25%. The batteries came with over 50% charge according to the EE-BMS Bluetooth App on my phone.
So as soon as I attached the charger, it showed two solid greens and two flashing greens.

At the end of 12 hours, the battery was 100% charged and the internal Cells were within 

0.008V ( 8mV) of each other according to the App.

With the first battery fully charged, I started on the second battery.

The App showed it was at 52% about the same as the 1st.

Leaving the Battery on charge, I took the day off to go to our Sailing Club's Family picnic ( I'll put a pic of my entry to the Dessert Contest below ) 

When I came back, the battery was showing somewhere above 75% according to the Charger's LEDs, but the App would not show the battery.

I exited the App and reloaded it, it showed the other two batteries, but not the one on charge. I removed the charger in case that was causing an issue, but nope! The battery's blue tooth connection would not show in the App.

At about 11pm I sent an email to Chins, remember, this is Saturday night here in South Florida. A reply was waiting for me since 1am Sunday morning!! 
The support guy gave a list of instructions to try and get the Bluetooth on the battery to wake up. No luck, Basically 'Bao' advised me to charge the battery for 10mins then discharge for 10mins several times. Did that. Didn't work.

Not being able to sleep, I had run that test around 4am. I responded to his (?) email and went back to bed. I also sent the screen shots included in this email that show the status of the battery that did charge ok.

By 10am Sunday, Bao responded that they would replace the battery! They would generate a return label sometime Monday. It arrived in my email Monday evening.

The battery is now in it's original box and UPS label applied over the old one. I'll drop the box off at the UPS store this morning on my way to work.

If this is the regular quality of support from Chins then it's worthy! 
Today is March 28th. Let's see how quickly the replacement battery arrives.

Oh, I didn't win the Family Picnic Dessert contest, but I gave it a good show.

It's a Pavlova, my Mom made these on special occasions, I think she would have been proud of my efforts. The best critique was seeing the empty serving dish before the picnic ended. 

I'll post an update once I know about the battery replacement arrival time.

No comments:

Post a Comment

Got questions or suggestions about our boat, our sailing or our adventures?
Leave a comment.