Planning on changing boat AGM house-battery (2x160Ah 12V) and Mastervolt charger to a Victron setup with inverter:
Going to purchase Multiplus-II, 3 x Orion-XS, Lynx Distributor, Cerbo-GX w/ display, etc. Will add Solar and MPPT probably later.
I think I’ve all the components more or less specified except the actual battery bank.
I’m planning on getting 4x200Ah Lifepo4, but the the price difference on Victron vs. e.g. LiTime, WattCycle, etc is quite big.
So the actual question:
With Victron I’d need to get the batteries and Lynx BMS, which then integrates nicely with the rest of the system, but the price is about 3600€ + BMS 700€=4300€.
LiTime and WattCycle for example have cheaper batteries with built-in bms, 4 pack of WattCycle for example is about 1500€ + I’d then need a Lynx Shunt + 310€ so total 1800€. But the batteries don’t have CanBus or serial interface so no CerboGX connectivity.. With LynxShunt I should get SOC of the bank to Cerbo, but what features will I miss if I save myself 2500€ and go with 3rd party batteries?
I guess Victron BMS can tell MPPT and Multiplus to stop charging/inverting if SOC becomes too high or low, but can Lynx shunt do the same?
Battery internal bms (when using 3rd party) should protect for overcharge/discharge also, similar to VictronBMS.
I don’t get visibility to cell level voltages but do I need to?
What would I miss going 3rd party or why should I push my hand deeper in the pocket and go for Victron NG batteries?
Any advice and constructive comments are welcome. I’m sure others have already had the same dilemma? What did you end up doing and why?
If you go with drop in batteries without comms make sure that you buy batteries with Bluetooth enabled BMS. The number of posts on here where people are having problems with 3rd party batteries and they can not troubleshoot is significant. Yes, you do need to know what your batteries are doing regarding cell voltages, because if they are out of balance the BMS can shut down and you do not know why even though the batteries are not charged at too high a voltage.
Will you have alternator charging, how are you going to manage this to make sure your alternator has a float voltage. How are you going to manage a load dump if all your 3rd party BMSs shut down charging.
Advantages of NG batteries & Lynx BMS.
Batteries are monitored on the Cerbo and VRM records the data for troubleshooting. This is useful when you are away from the boat.
Lynx BMS controls external alternator regulators such as the Wakespeed WS500 and shuts them down safely before the BMS isolates the batteries avoiding over voltage on a load dump.
Cerbo GX can control all charge sources as a single unified charge source as requested by the BMS.
The Lynx BMS has a contactor, I would say that it more robust than solid state switching.
The BMS monitors cell balance and only keeps the batteries at full voltage until the cells are balanced. This is often less than 3 minutes. For 3rd party batteries you have no way for this type of fine control so you have to either hope they are being balanced or set the end of absorption to hold them at a higher voltage for longer.
There is only 1 BMS so you have no concerns of the VMSs getting out of synch with each other.
Disadvantages of Lynx BMS / Victron batteries
Cost.
Victron batteries do not include heating if that is required.
Space taken up by the system.
I have 2 x 300Ah NG batteries, Lynx BMS and WS500 alternator regulator for 6 months now. Rest of the system is all Victron. Really pleased with the system and glad I installed it. Cost wise, it was an indulgence.
The Lynx Shunt can not tell things to start or stop charging, but it can provide a reliable SOC so you can set SOC shutdown on the inverter. You can also write your own control into the Cerbo using a feature called Node-RED to control charging etc from SOC.
Thanks. Really good information to take into consideration.
I’ve 120A Alternator connected to engine battery (AGM) and based on other posts, I believe it should work as a buffer for load dump. Although the Wakespeed WS500 looks interesting. Need to take that also into consideration.
I’m planning on adding 2 x 50A Orion XS to replace a VSR, so those will handle the charging from alternator side to house/leisure batteries. There will also be an additional Orion to handle bowthruster battery (AGM) charging from house bank.
I was taking some measurements at the boat yesterday, and the space I was thinking of putting the other 2x200Ah batteries is not large enough. I might have to go your route and put 2 x 300Ah batteries (if space permits) instead of 4 x 200Ah.
Question about the WS500 that you mentioned, would that be connected to the engine battery that is being charged directly from the alternator, or the house lithium bank that is charged via Orions? Or both, CAN connection to cerbo and the current sense to engine battery? If so, then I’d need a shunt on the engine side also?
WS500 would be nice, but most likely Orions should take care to only charge house battery when engine is running and the engine battery to buffer the voltage spike when house bank is full and bms disconnects the charging?
If your alternator charges the engine start battery then you have Orion XS to the lithium you do not need an alternator regulator like the WS500. You only need this if the alternator charges the lithium direct, which mine does. The lead acid protects against load dump. The Orion XS would be controlled by Lynx BMS through the Cerbo but will be OK with third party batteries. The only thing to be aware of is a 120A alternator may only be goo for 80A continuous without overheating, so you may need to dial the Orions back and see how things go, unless you know the alternator is rated gor 120A hot.
LiTime, WattCycle and other batteries of their ilk have crap BMS’s in them. We’ve had quite a few customers over the years find out the hard way and ask us to replace them. The LiTime batteries, for example, had issues where the BMS would shut off if charging at a higher rate (i.e. 0.5C) and disconnecting the charging device. We saw the same issues with SOK batteries. When the generator turned off or shore power was removed, the batteries would shut down.
Do I know if the very latest versions still have these problems? I do not, but since the BMS is the most important part of a lithium battery, I won’t risk it with customers. And I absolutely wouldn’t risk it on a sailboat in open water.
Victron batteries are more expensive to be sure. In a larger system that price evens out more when considering the extra functionality of the Lynx BMS. In smaller systems it might be hard to justify. I don’t know the battery market for the EU so I can’t recommend any specific drop-in batteries that have a high quality BMS, but I’m quite certain they are out there. Maybe someone from Europe can chime in.
If you are sailing in open waters, my suggestion is to pay more for better batteries. Having closed-loop communications is nice for troubleshooting issues as well since you get more battery data visible to VenusOS on your Cerbo.
If you are using the stock engine alternator(s) with lead-acid starter batteries then you won’t use an external regulator. If you are adding a secondary alternator that connects directly to the DC buss or house batteries, then you will need an alternator regulator and I would highly recommend batteries with a BMS that can disable charging from the alternator immediately if the batteries disconnect for some reason.
One other piece of advice: go with a 24V house battery bank at the minimum. 12V wiring at high currents sucks for many reasons.