Ben Stein, over at Panbo, has just published a good review of the new Victron NG LiFePO4 batteries and related BMSs, well worth the time to read for most any cruiser who is even faintly interested in lithium batteries.
I won’t try to duplicate the excellent job Ben has done describing what makes this new system from Victron exciting, but rather I’m going to highlight a few things that jumped out at me as probably1 making this a good option for offshore cruising boats, particularly when paired with one or more Lynx Smart BMS NG(s):
Assuming this system proves to work as described by Victron, and we build a system with two paralleled NG BMSes with a NG bank split between them, is the seamanlike system requirement for a lead acid bank in series to power critical loads eliminated?
There can still be good reasons to include at least some lead acid battery capacity in a system with paralleled Victron’s BMSs. One example is including a charging source (such as a Watt & Sea hydro generator) that is not capable of DVCC into an otherwise DVCC-enabled system. One way to accomplish that is to have the non-DVCC charger connected to a separate battery that is in turn connected to the main lithium bank with a DVCC-capable DC-DC charger.
Hi Mark,
Good point and I like your solution better than compromising DVCC at recommended here: https://support.wattandsea.com/hc/en-us/articles/115004346689-Can-I-use-Lithium-batteries-with-the-Watt-Sea-converter
Hi Jonathan,
Great minds think alike! I have been wondering about exactly that myself. For a big boat with a deep pockets owner, maybe so, but for smaller boats the serial backup lead acid is a lot less expensive option.
I consider DVCC to be one of the key competitive advantages of going with a Victron lithium battery system, but something that Stein fails to mention is the very limited selection of DVCC-capable components that are also fully ABYC compliant. This is particularly true for chargers, inverters and inverter/chargers. Unless Victron’s certification efforts are ahead of their documentation, the only options for these that satisfy the ABYC’s requirements (e.g. UL 458 for inverters and inverter/chargers) are a small selection of MultiPlus and MultiPlus-II inverter/chargers that include only models with 120VAC output, no more than 3000VA rating, and only 12V or 24V.
Of course, bigger systems can be built using the options to combine multiple inverter/chargers, and 230/240V can be achieved in a couple of different ways, but an insurable, ABYC-compliant, DVCC-capable system that includes an inverter running on 48V batteries does not appear to be possible at this time.
I still really like Victron gear and the parallel redundancy capability of the BMSs in particular, but potential users who want an ABYC-compliant system should be aware that their options are very limited and designing such a system requires careful reading of the ABYC standards and Victron’s documentation and certification statements.
Hi Mark,
Are you saying that UL 456 is a requirement for ABYC? If so, I guess you are right, but I did a quick google search and could not find that link.
That said, even if UL456 was required, I guess I would not be overly worried about that given that Victron is a European company and I’m would guess compliant with all CE and ISO requirements. Assuming that’s true, I can’t imagine an insurance company having a problem, particularly since ABYC is, at least as far as I understand it, not a real government standard but rather a set of industry guidelines, whereas CE is, I think, a European Union standard.
Yes, A-31 Battery Chargers and Inverters requires UL 458:
31.5.4.2 All marine power inverters shall meet the applicable requirements of UL 458, Power Converters/Inverters and Power Converter/Inverter Systems for Land Vehicles and Marine Crafts, and Supplement SA, Marine Power Converters/Inverters and Power Converter/Inverter Systems.
31.5.5.1 Devices that serve as both battery chargers and inverters shall meet the requirements o fboth battery chargers and inverters (see A-31.5.3 and A-31.5.4).
Full ABYC compliance is something that may be negotiable with an insurer, but if they want your boat to be ABYC compliant, then you can’t use many Victron products.
Hi Mark,
Seems like Victron are on this anyway: https://intelligentcontrols.io/blogs/technical-articles/victron-inverter-charger-ul-certification-cheat-sheet
That document isn’t entirely accurate, and there has been no change in it or Victron’s documentation for the items listed as “under progress” or “pending certification” for many months. Further, there is no indication that the higher power and voltage products will ever receive UL 458 certification. Rather, they are being certified to UL 1741, which is relevant to shore-based, grid-connected operation, not to ABYC compliance and marine use.
Wow, I really should have scoured the Victron docs before commenting based on the last time I did so. As of the end of February, there is now one 5000VA option that is UL 458 compliant: https://www.victronenergy.com/upload/documents/Certificate-UL-458-Quattro-12V-5kVA-120V-VE.Bus.pdf
A correction: There is one way to build a 48V system with an inverter/charger that is DVCC-capable and ABYC-compliant. The MultiPlus-II 48/3000/35-50 120V meets that spec.
https://www.victronenergy.com/upload/documents/Certificate-Safety-UL-458-MultiPlus-II-12-24-48V-3000VA-120V-080525.pdf
“Meets all ABYC requirements for fully automated BMS controlled disconnection.”
One detail on this: ABYC does require battery disconnect switch(es) between the batteries and the BMS that the Lynx Smart BMS NG cannot satisfy on its own, even though such ABYC-compliant battery switches do not appear in most Victron system diagrams.
Hi Mark,
Sure, that’s true, but adding a battery switch is no big deal.
Yup, not a big deal — just a detail to be aware of that is not obvious from Victron’s documentation.