asked
Hello. Did somebody try to connect a Quattro with LTO batteries? If yes, is it necessary to change the settings by computer or PID are enough? Then how do I connect the BMS? Thank you
Hello, i have connected my MultiPlus to 25s LTO battery. 35ah by cell. It work very good, high efficiency charge discharge. I have bms (1.5v to 2.8v) I hace configure MultiPlus 50v
Min and 62.5v Max voltaje
Hello javialcala.
Thank you for your answer and congratulations for your installation. Please I have some questions.
1. What is the reference of your BMS?
2. How did you change the settings of your multiplus : MK2, CCGX or DIPs?
3. I don't understand how I must connect the BMS to the inverter?
4. Did you also connect a solar charger?
Sorry to take your time but your advices will be very precious. In case, you can reply directly to me: chrissementpy@gmail.com
Thank you again.
Hi, this is my bms https://es.aliexpress.com/item/32927176673.html?spm=a2g0s.9042311.0.0.a68f63c0HQhEHE (you can check instalation diagram in this link too )
I change settings in my multiplus II 5000va using remote vconfigure (you can upload configuration filed) to your in vrm web portal. (device list, remote veconfigure).
You change this configuration file using veconfig3 victron program.
I have two solar fronius solar charger. 8,2kw each . 16.4 total. system ac in coupled.
I have been seriously thinking about trying this, but ultimately did not attempt to simply due to the price of LTO cells vs energy density vs overall cycle life compared to LFP or NMC, which just didn't seem to make sense to me, at least for my application... That being said, I don't see why it would not be possible depending on what model Quattro/Multi you are using. I am using 24V Multis, which have a maximum input of 33VDC and can charge up to 32VDC...
LTO cells have a 2.3-2.4v nominal, 2.8v max, and around 1.6v-1.8v cutoff voltage to my knowledge depending on the manufacturer.. For my inverter I probably would go with an 11S configuration using LTO cells, which would give me a maximum voltage of around 30.8v absorb, and low voltage shutdown around 19.8v.
This is a pretty wide range which I don't like about the LTO cells, but I think will still work without any major issues. You would likely need a custom BMS that will not connect with the Victron, and would need to be capable of controlling it's own internal charge/discharge protection switch. I have had good experience with the Bluetooth Enabled BMS boards from China, simmilar to this one here which unfortunatley does not have Bluetooth, but is for LTO cells: https://www.lithiumbatterypcb.com/product/4s-or-3s-12v-lifepo4-battery-pcb-for-14-4v-or-14-6v-lifepo4-battery-of-back-up-power-bms-and-power-inverter-battery-protection-circuit-2-3-2/
These manufacturers usually can offer you a custom solution for your needs if you contact them however.
ee21, thank you so much for your explanations. This is very interesting. I will see that soon.
Good day!
