validate my LiFePO4 upgrade

[rgleason]

PS. The Battleborn have no provision for controlling an external relay, so the Wakespeed becomes the better choice for faster charging.

[rgleason]

Originally Posted by newhaul

Except its a full 30a through the dc2dc the efficiency numbers are alternator derate numbers due to heat. And since the 30amps is less than half the alternator output the heat throttling will have no effect .
On the other front I agree that 30 amps is a bit anemic for 200ah worth of bank .
Giving a .15C charge rate . He does have solar as well.
Personally I would like a 60 amp b2b to take full advantage of the alternator output. ( but thats just me)

Newhaul, your are right. I got it backwards.

I guess I should not have de-rated for its 87% efficiency, that is already taken account of in the 30a output.

Actually, the alternator will have to charge 1/87% more amps, or 1/.87= 1.15. So the alternator willl have to only provide 1.15 x 30a = 34 amps.

Which for a 70a alternator derrated by 70% for longevity and continuous hot running is 49amps alternator output. So he could use a 50a DC/DC charger to make it faster charging and a 60a would be even better because it is best to run electrical at below full output for longevity.

[rgleason]

If you were to use the Wakespeed WS500 Regulator to protect Battleborn these are the appropriate settings
Note that
That "Zero Output Technology" should be enabled to protect the batteries.
That Battleborn does not have any external relay control or BMS integration, and so Wakespeed recommends using
"proven mitigation measures such as keeper batteries and avalanche diodes are recommended to ensure minimal damage from BMS shutdown."


Well I guess the Balmar 614 regulator will be just as good in this situation using Battleborn batteries with no BMS integration.

[newhaul]

Originally Posted by rgleason

Newhaul, your are right. I got it backwards.

I guess I should not have de-rated for its 87% efficiency, that is already taken account of in the 30a output.

Actually, the alternator will have to charge 1/87% more amps, or 1/.87= 1.15. So the alternator willl have to only provide 1.15 x 30a = 34 amps.

Which for a 70a alternator derrated by 70% for longevity and continuous hot running is 49amps alternator output. So he could use a 50a DC/DC charger to make it faster charging and a 60a would be even better because it is best to run electrical at below full output for longevity.

Exactly but for the actual expected run times along with solar the 60 amp unit ( which in the case of renogy the 60 amp b2b is cheaper than their 50 amp unit. Would in my opinion be a better choice if I were building from scratch .with his 70 amp alternator

[Pete7]

Originally Posted by Randy P

Yikes! Harsh, dude, But you are correct in your assessment of my reason for the Orion. Plus, my engine-on cruising is usually no more than 2-3 hours and the solar panels are also limited via the mppt to <30a and I also have a slip with shore power to run the battery charger.

Randy, looking at the 2AWG wire from the battery switch to the BMS, is this for emergency starting use only? Once running how do you ensure it is moved to the engine start position in a clockwise direction rather than anticlockwise, ie, no temporary moment when there is no batteries connected to a charging alternator.

Why do you think the alternator will have loads of 20A for the house and 20A for the engine start battery. The Orion will take 30A if it can but the engine battery nothing after a couple of minutes to replace the amount an engine start took. There was a video of a medium sized yacht engine being started and monitored by a NASA BM1. Sure the Amps read 102 during the start for a couple of seconds, but the total AH used was minimal.

My battery temperature sense is connected to the MPPT via bluetooth. Is yours still connected to the MPPT? if so is there a risk that the lithium setting on the MPPT will be altered by the data from the battery sense, particularly temperature? Using the Lithium settings might disable this temperature adjustment, but I guess we need to investigate this further just to be certain.

What stops the MPPT from dropping to a float and continuing to charge the LFP bank when you are not in use. My understanding that LFP shouldn't be float charged. Another battery switch right next to the battery to "throw" as you leave the boat for more than a few hours might be a cheap solution.

What did you use to create the wiring diagram?

like you I am collecting information and taking pre-installation steps to sort out the charging sources first. After all a LFP bank is just a store of energy, other parts generate it.

[Pete7]

Originally Posted by newhaul

( which in the case of renogy the 60 amp b2b is cheaper than their 50 amp unit.

Ha, nice spot

Renogy are not well known in the UK, how do they compare to say Victron for quality and efficiency?

Shame about the 20% plus import charge

Pete

[newhaul]

Originally Posted by Pete7

Ha, nice spot

Renogy are not well known in the UK, how do they compare to say Victron for quality and efficiency?

Shame about the 20% plus import charge

Pete

They are good units . The true metric is in the warranty and after purchase response from the manufacturer. I have always had good response from renogy wrt panel failures .

One little caveat I have is many people don't pay enough attention to the specifics in manuals. For i stance the renogy 50 amp b2b with mppt solar controller.
Deep in the manual it states if you are just using the alternator hookup it will carry 50 amps but if it has solar hooked up it maxes out at 25 amps for each in tandem for a total of 50 amps.

[Robhwa]

Originally Posted by newhaul

They are good units . The true metric is in the warranty and after purchase response from the manufacturer. I have always had good response from renogy wrt panel failures .
One little caveat I have is many people don't pay enough attention to the specifics in manuals. For i stance the renogy 50 amp b2b with mppt solar controller.
Deep in the manual it states if you are just using the alternator hookup it will carry 50 amps but if it has solar hooked up it maxes out at 25 amps for each in tandem for a total of 50 amps.

I have two Renogy 50A 12to12 with MPPT setups, one in my camper, and one in my yacht (ha!). I put a switch on my truck system to shut off my solar inputs when driving because I did read the manual, but it doesn't seem to actually be limited to 50A@12V total.

In fact, the total charging can go up >60 amps when solar is really cranking in my camper system, cool, breezy w/ direct sun usually. I suppose this is because the amps coming from the solar can be >20V so 50A@20V when converted to 12 volts provides more than 50A@12V. My truck CAN supply >100A, but I don't have the cables for >100A anyway, and 50A protects the alternator from overheating. My boat engine only charges at 17 amps, so no stress on that system.

Another thing good buried in the manual. The solar panels will charge the starting battery, which is good if your system sits for a while. You don't need to disconnect the starting battery as I used to, or hook up a solar maintainer, as I eventually did. That is already built into this system. I'm overall happy with this setup, though clearly, sometimes I might like to charge my 200AH of LiFePO4 faster.

One additional, possibly major, disadvantage for some is that the Renogy is 12V ONLY. You can't bring series-wired panels into the controller to make your wiring more efficient, and you can't series wire batteries either, say to run a 3000W inverter from 24 or 36VDC. I resorted to a 12to24V converter to run my 24V electric trolling motor. This is definitely not ideal.

[Randy P]

Originally Posted by Pete7

Randy, looking at the 2AWG wire from the battery switch to the BMS, is this for emergency starting use only? Once running how do you ensure it is moved to the engine start position in a clockwise direction rather than anticlockwise, ie, no temporary moment when there is no batteries connected to a charging alternator.

Why do you think the alternator will have loads of 20A for the house and 20A for the engine start battery. The Orion will take 30A if it can but the engine battery nothing after a couple of minutes to replace the amount an engine start took. There was a video of a medium sized yacht engine being started and monitored by a NASA BM1. Sure the Amps read 102 during the start for a couple of seconds, but the total AH used was minimal.

My battery temperature sense is connected to the MPPT via bluetooth. Is yours still connected to the MPPT? if so is there a risk that the lithium setting on the MPPT will be altered by the data from the battery sense, particularly temperature? Using the Lithium settings might disable this temperature adjustment, but I guess we need to investigate this further just to be certain.

What stops the MPPT from dropping to a float and continuing to charge the LFP bank when you are not in use. My understanding that LFP shouldn't be float charged. Another battery switch right next to the battery to "throw" as you leave the boat for more than a few hours might be a cheap solution.

What did you use to create the wiring diagram?

like you I am collecting information and taking pre-installation steps to sort out the charging sources first. After all a LFP bank is just a store of energy, other parts generate it.

The 20A loads are my calculations based on the total of all amp loads from fixtures using the 12V DC current from either the engine battery (100AH FLA) or house bank (2 X 100AH LFP). My biggest load user is the AC/DC Norcold refrigerator which takes 3.8A DC and cycles 2-3 times/hour on hot days away from shore power. It takes 0.8A AC. I’ve sized the solar and all components based on my 20+ years experience with this little power cruiser. I agree that the 30A max charging sources of my MPPT and DC/DC charger are a bit weak, but they’re adequate for my needs.

I used Microsoft Power Point for the diagram.

The 2AWG cable and 6AWG cable sizing was done by checking the Circuit Wizard app via Blue Sea Systems, as well as, again 20+ years experience with this boat and its needs.

Now all I have to do is keep this 1977 Chrysler Marine 318 running!

[Randy P]

PeteZ - My battery sense was connected to my original FLA house bank, but I’m going to use the Victron 712BMV connected to the new LFP house bank, as well as the temp sense wire for the BMV. I’m going to use the Battery Sense on the FLA engine battery. I really like the Bluetooth connection on the Victron appliances, so I’ll be able to get data and control via my iPhone or iPad while on the boat.

[Dalliance]

I recently added 800 amphr LifPo4 Battle Born batteries to my cat. I’m not trying to sway you, but when I was in the planning stages of my battery system i talked a lot with BB to validate my design and they saved me money on some items and suggested spending more on others. One thing O did not initially plan for was the increased size of wiring due to the larger and longer bulk charges the lithiums could take from 120 amp alternators or the 1450 watt solar array. Good luck on your install!

[Randy P]

I agree about the help and pricing I got from Battle Born. I got replies back from my one contact their (Brandon Newman) within less than 12 hours, and I had a LOT of questions. He put together a bundle of products for my quote which included 2 100AH BB batteries, Victron Orion DC/DC charger, Victron 712 Battery Monitor, Victron IP67 AC charger, and even the Temp sensor for the 712. Bottom line is I saved money on all items. I’m but pushing the Victron brand but I really like the Bluetooth feature on all their “smart” products and was very impressed with their MPPT controller which I installed last year for the new solar panels I also installed.

I agree that LFP is far more expensive than FLA, AGM, etc., and I am not confident enough to tackle building my own LFP from cell, BMS, etc. But, bottom line for me at the tender age of 76, is I don’t want to continue replacing 130-140lbs of house bank batteries every 3 years and I want safety and convenience to carry me forward into this “creeping decrepitude”

Happy New Year!

[JimJohnston]

Hi MooGroc
if you change your mind and decide to add an alternator and a regulator I have, from my spare unused inventory, a 100A marinized alternator and a Balmar MC-612 H regulator neither of which have been used and that I wish to sell. Both for $275 plus shipping.

Jim

[shelbybob]

The dc to dc charger will keep your life simple. You can keep the alternator set up you have now and when your engine runs, your lifepo4's get charged. Thats how my set up is. Im using a renogy 40a dc to dc and solar on my 840ah bank.