Anyone w/ Lithium LifePO4 House Battery Bank Conversion Experience

[rgleason]

Originally Posted by newhaul

Issue ; Not even water resistant. Really not a good idea for electronics on a boat in a saltwater environment without adding protection accordingly. Why not spend the same on a good bms that is . The one I have shown and linked to several times has active balancing as well as HVC and LVC built into the unit not to mention its waterproof .

Good points. Ok. I know I can find it with a search.

Here is the order for the BMS, but it seems pretty generic.
https://www.cruisersforum.com/forums...2&d=1536517108


I have a question, does this BMS have a no/nc contact which can be used to activate a relay to disconnect the LiFePo for protection (overvoltage, overcurrent, undervoltage, under current, temp?)


What relay did you use?

[CarlF]

The drop-ins have come a long way in the last two years and 300 AH drop-in's are now very common in big cats as they are the same size as the 8D AGM's. The most popular brands for the 300's seem to be Relion, LifeBlue, and Lithionics. They come with 5-10 year warranties. Pretty amazing.

Some things to check:

1) That the charge rate is high enough. Some brands only take a 50amp charge. If you have 3 batteries you can only charge 150 amps. Many boats charge much more than that.

2) That you protect the alternators from blowing their diodes if the BMS turns the battery off. This is just like turning off the main battery switch while the engine is running. One easy way to protect against this is by having an AGM start bank that is connected to the house bank by a combiner. For belts and suspenders it's also good to install a zap-stopper or a Sterling Alternator protector.

3) Use big cables and fuse with a T-class fuse within 7 inches of the positive terminal.

4) Disable temperature compensation in your chargers

5) This is a lot of energy - if you are not very experienced hire an electrician to help you or at least look over what you have done.

[newhaul]

Originally Posted by rgleason

Good points. Ok. I know I can find it with a search.

Here is the order for the BMS, but it seems pretty generic.
https://www.cruisersforum.com/forums...2&d=1536517108


I have a question, does this BMS have a no/nc contact which can be used to activate a relay to disconnect the LiFePo for protection (overvoltage, overcurrent, undervoltage, under current, temp?)


What relay did you use?

No that was for my 25ah test bank .

This is similar to the unit I have on my 250ah bank . I just went factory direct for mine

https://www.electriccarpartscompany....agement-System

[more]

Originally Posted by newhaul

Issue ; Not even water resistant. Really not a good idea for electronics on a boat in a saltwater environment without adding protection accordingly. Why not spend the same on a good bms that is . The one I have shown and linked to several times has active balancing as well as HVC and LVC built into the unit not to mention its waterproof .

all battery is in GRP IP69K case with Automatic Pressure Relief, Anti-Explosion For Battery Pack

[Michael Cobbe]

Lithium-ion batteries commonly used in consumer electronics are notorious for bursting into flame when damaged or improperly packaged. ... "If the battery is damaged and the plastic layer fails, the electrodes can come into contact and cause the battery's liquid electrolyte to catch fire.


They have aso cused fires in planes and cars

[Davidasailor]

Originally Posted by Michael Cobbe

Lithium-ion batteries commonly used in consumer electronics are notorious for bursting into flame when damaged or improperly packaged. ... "If the battery is damaged and the plastic layer fails, the electrodes can come into contact and cause the battery's liquid electrolyte to catch fire.


They have aso cused fires in planes and cars

Not all lithium batteries are the same chemistry. The batteries used in consumer electronics hold a higher energy density but are more dangerous when mishandled or damaged. LiFePo4 is not as high risk from that standpoint.

[rgleason]

Note that the thread is titled LiFePo4. These are considered Lithium Batteries, but they have different characteristics than Lithium-Ion.

@Newhaul Thank you that helps. I think these are similar to the Daly BMS Balance 4s 3.2v Bluetooth Waterproof that can be found on Alibabba. (can't find one now on Alibaba).

4S 80A 100A 200A 12V 3.2V LiFePO4 Lithium Battery Protection Board BMS Balance

Also I think the Alibaba Bluetooth Smart Deligreen BMS 3.2v 12v

• Brand Name: QNBBM
• Accessory Type: Battery Accessories
• Model Number: DG4S-120A150A200A
• Application: LiFePO4/LiNCM
• battery series: 4S
• over charge protection: yes
• short circuit protection: yes
• over discharge voltage: yes
• with heat sink: yes
• with temperature monitor: If you need pls tell us
• charge port and discharge port: common port
• constant charge current: 120A/150A200A/250A
• peak discharge current: 350A/400A/530A/600A
• Delivery time: 1 business day
• With balance function: yes

But this one is not waterproof. However this one is IP166
Bluetooth Smart BMS 4S 150A 200A 250A LiFePO4 Battery BMS for 14.6V Battery pack with Bluetooth CAN communicatio UART RS485

• Brand Name: QNBBM
• Accessory Type: Battery Accessories
• Origin: CN(Origin)
• Model Number: DG4S
• Application: 3.2V LiFePO4 battery
• battery series: 4S
• over charge protection: yes
• short circuit protection: yes
• over discharge voltage: yes
• with heat sink: yes
• with temperature monitor: can be customzied
• charge port and discharge port: common port
• constant discharge current: 150A 200A 250A
• Waterproof: IP66

How would I connect a relay to disconnect the LiFePo Battery on overcharge, discharge etc, in a Franz Veldman Hybrid-Lithium Configuration?

Or should I have separate charge, load and negative busses with relays?

What relay should I use?

[rgleason]

I now think a "common port" BMS will just control one relay which should be normally open, so that it will fail open to protect the battery. This configuration would be like the very simple Franz Veldman Zwerfcat Lifepo4-Hybrid configuration which uses a single charge and load bus, so that it is difficult for the system to monitor and record charging and load discharging.

If you want to monitor charging and discharge loads separately and have the history available, I think you need to have a separate charge bus and a separate load discharge bus, which means you need a dual port BMS. Why would I need this I ask?

I am just going to have Alternator and Solar charging, and if I know the SOC of the LiFePo4, I will know when I need to charge with the Alternator. Why would separate monitoring with a dual port be useful?

---Later: Now I realize that if the LiFePo is disconnected for overcharge, with a single bus, I will no longer be able to power my equipment because it will be disconnected! Therefore a separate discharge bus and relay controlled by the BMS, to disconnect when the LiFePo4 is low, is also necessary. Therefore a dual port BMS is useful.

What are the additional complications of this dual port, dual relay, charge bus + discharge load bus setup?

[rgleason]

Reviewing Franz Veldman's Lithium Implementations Page which shows the various alternatives and pros and cons in a clear way with diagrams, I can see that the dual bus topology with two relays has

1. No FLA batteries shown to take alternator output when the LiFePo4 is cut off on overvoltage & overcharge, so the alternator needs to be protected by automatic disconnection of the field current. I wonder there is a relay that would have some passive contactors to disconnect field current at the same time the relay opens?
2. When the LiFePo4 have reached over discharge voltage, or max DOD depth of discharge then all the equipment loads are disconnected which is fine, but there is no backup FLA in this topology. However one distinct advantage to this topology is the equipment can continue to use the LiFePo4 after the batteries have been fully charged.

It appears that we would need to connect 12vdc FLA batteries to the charge bus and the discharge bus (2 FLA) to solve the these problems.

[JPS31]

Hi, I have a bad experience to share about EVLITHIUM company which sells WINSTON & CALB cells. I ordered from them with delivery to my home, delivery cost was 450US then just upon arrival I noticed that the delivery will be at the port.... And they say that they cannot deliver at home in New Zealand... Finally they asked for 900 US$ to deliver at home !!!!

[kmacdonald]

If you have to ask, LiFePO4 should not be a consideration for you.

[mcarthur]

Ouch. That's really bad. I'd not be willing to risk that happening, so they're out (though this is only one data point)

[kmacdonald]

Originally Posted by mcarthur

Ouch. That's really bad. I'd not be willing to risk that happening, so they're out (though this is only one data point)

It's not that it's bad, it's that it takes a lot of research and understanding. Mistakes are costly and turn key systems have a history of failure not to mention the cost outweighing the benefits for many. LiFePO4 does check all the boxes except for ease of implementation. Newer off the shelf equipment has significantly reduced the costs and complexity but the entire system needs to be engineered properly. A lot of drop in battery marketing gives the allusion that you just drop them in and everything will be a bed of roses.

[fxykty]

Originally Posted by JPS31

Hi, I have a bad experience to share about EVLITHIUM company which sells WINSTON & CALB cells. I ordered from them with delivery to my home, delivery cost was 450US then just upon arrival I noticed that the delivery will be at the port.... And they say that they cannot deliver at home in New Zealand... Finally they asked for 900 US$ to deliver at home !!!!

I ordered from a different company and we were able to pick up from a port freight forwarder located in South Auckland. Is that your situation? There is no pick up at ports - unless you’ve got an entire container.

[bgallinger]

I replaced my 4 x lead acid 100Ah batteries with 3 x Canbat CLI100-12 12V 100Ah deep cycle lithium batteries. I have a 100Ah Balmar alternator with a MC-614 external alternator so I was able to adjust the charge settings for the alternator.

I made 2 mistakes:
The first was not adding a dedicated AGM engine start battery. AGM is preferable as the charge settings are similar with Lithium.
Second mistake was not making provisions to prevent the alternator from burning up.
I have since added a 100 Ah AGM engine start battery and Balmar says they are coming out with an Alternator Protection Module before the year end.