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harryboat avatar image

300ah Smart lithium 24v setup

I have the possibility to put 8 or 10 x 300ah smart lithium (victron) batteries into my boat and my boat is 24v. I don't have Victon chargers as they are Mastervolt and these will be programmed to the lithium charging settings.

My question is what is the best way to connect these 8 or 10 batteries using the bms because I understand that the bms system has limitations and wondering how this would affect the setup and ways around this.

Please dont tell me that I should choose different batteries as these are my option.

If anyone can help I would much appreciate it

Lithium Battery
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3 Answers
Vance Mitchell avatar image
Vance Mitchell answered ·

From what I can find online, it says that you can connect 5 batteries in parallel and 4 in series. That allows for up to 48v 1500Ah.

10 batteries seems to be the maximum for 24v, with 5 lots of 2 in series.

I couldn’t find if there is a preferred connection sequence for the BMS but it definitely mentions it being possible. (The battery manual does show a 2s3p connection which gives a good indication).Link to manual

I would definitely consider using bus bars for positive and negative connections and keeping all cables identical in length to help ensure equal charge and discharge across all batteries.

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harryboat avatar image
harryboat answered ·

Thank you. I understand and appreciate your comments.

I understand that with the BMS there is a limit to how many batteries it can work with.

If there are 10 x 300ah smart lithium for example and they were connected in 24v could 1 x BMS control all batteries? If not how could it be connected?

I may change the mastervolt and put a Quattro 8000w 24v instead with CCX etc..

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That's a good question. I had overlooked the quantity in your original post. According to the manual, it states up to 5 batteries in parallel. You may want to get clarification from Victron or a dealer on here as I'm just an end user.

nebulight avatar image
nebulight answered ·

The beauty of the Victron system is the ve.bus bms directly interfaces with the batteries and inverter charger. Since your other gear isn't victron, you won't have that option. Do you know if your chargers have remote on/off connectors? The external BMS is used to control other devices however depending on the device, that may not be possible without a remote on/off. There are Allow to charge and Allow to Discharge ports. You'd wire the allow to charge to your chargers and Allow to discharge to your inverter and other DC loads.

If your gear doesn't have remote on/off one option is to use a Victron MiniBMS in conjunction with a Cyrix to enable/disable the other chargers. However you should double check to make sure your MPPT would be okay with disconnecting from the battery on a regular basis. You can also use a Cyrix load (or battery protect) for your small DC loads. Your inverter is going to be the big question. Is it an inverter or inverter/charger? I'm only aware of Victron having the ability to control the inverter and charger separately with an external BMS. I wouldn't run an inverter through a cyrix, at least not without some type of pre-charge circuit.

Sorry I'm in the US and we don't have Mastervolt here so I'm not familiar with their product line.

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