Brak...remote deep cycle battery near the thruster is a good idea. Lets say 100ah group 30. Two options:
1.Echo charger which will recharge it after house bank is fully charged.
2. Separate small 3 stage charger of 20amps or less that can be run off your inverter. A bit less efficient but makes a lot of sense in terms of ease of wiring.
Now even a 2kw thruster is gonna draw 167 amps...or about 3amphours per minute of use. Thus a 100ah battery will give you about 15 minutes of use before recharging is required...so sizing your bank to the amps required needs to be considered as well...but 15 minutes is a LOT of use on a thruster. If you need a bigger thruster for your boat...then you start getting into a need for a bigger battery capacity.
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