This was my source for the LiFeYPO4:
It seemed EV-Power has much better prices, - but I assume the LiTrade prices include already the German VAT of 19% - so they are almost identical. It's the law in Germany
, than online prices in consumer accessible stores have to show the retail price
including the VAT.
I have to figure out, what BMS is capable to handle the 24 cells. Probably one have to go bold with something like this: LiGoo FT11 BMS
, I also found this one at EV-Power, BMS-2405
, but it is way to weak for high-current applications (0.5A balancer current
, maximum capacity 100Ah/cell).
Well, to keep the hybrid and pimp it up wit LiFeYPO4 even with a higher capacity has some charme - especially if you go directly for the whole charging
system to 72V and use the inverter
from 72V to 220V - also for the fridges / freezers / galley
(induction + oven
/ micowave) and keep a small (100...200Ah) 12V LiFeYPO4 only for the navigation electronics
and lights, re-charged from the 72V main batteries
You would get also, as I read after some research
, a decent charge from the propellers while sailing, but miss around 1kn in speed. The regeneration starts at 4.5kn (6A) to 9.6kn (36A) @ 72V, this sums up to re-charging between 430W...2.600W using the wind
alone, if you add a decent solar
array of some panels
around 1.200W - 1.500W you probably will not need the generator
at all or only in heavy weather
, you would get enough energy even at anchor
to run all gadgets on board and need then propane
only for the BBQ. The total usable capacity with 130Ah cells is around 15kWh, so one day sailing
with decent winds could re-charge the battery
bank - or you stay one week anchoring
in the sun for the same purpose.
It seems to be a good idea not to dismiss the hybrid too early. The only disadvantage so far is some speed you'll miss, especially in light winds due to lack of folding props or when the batteries
Well, thank you again for pointing me in this direction. I definitive need to make some more research
on the available 72V inverter
devices in the range of 3kW...6kW.
My original idea was to have a conventional propulsion
and replace the house batteries by 12V / 700Ah LiFeYPO4 (4 Cells) + 1.200W Solar
+ 2 x 3.000W 12V Victron Multi-Plus Inverter/Chargers, getting rid of the propane
in the galley
(Induction cook top + microwave/convection oven), powering occasionally the water
maker, washer/dryer, diving compressor
and hot-water heater
out of the lithiums + solar with a small 4kW emergency generator
when at anchor
for a longer period of time in bad weather
. The starter batteries could be used in case of LiFeYPO4 failure as an emergency
replacement for the navigation electronics
/ lights - re-charged by the alternator
of one of the engines and the solar array.
I would have chosen the 2 Multiplus because they have a 120A charger
each, so with a small 4kW emergency generator you can re-charge the bank in less then 3 hours and also have up to 220V / 10kW if needed by combining the power of the generator with the output of the 2 inverter using the power assist option for the heavy duty stuff if needed.
It would probably sum up in the end up to 12k€ investment too, depending on what is already available on board.