On-board chargers are popular with the fishing owners, as the charger is typically used to charge the trolling motor batteries in the bow of the boat. These chargers are usually built-in and are extremely handy for maintaining those batteries. These motors may be either 12 or 24 volt, requiring both batteries to be charged. Not all fishermen connect the engine's start battery to an on-board charger. Some do, some don't. If your boating habits call for the boat to travel longer distances, the engine's charging system will usually maintain the battery charge without any additional on-board charging required. If you run a lot of electronics off the engine's start battery and don't travel much distance on the 150 engine, it's possible that the engine may not maintain the charge on the cranking battery at the optimal level. In that case, you should consider an on-board charger for the start battery. The 150 engines of this year had two different charging systems. The base 150 had a 10 amp battery charging system. If the engine was the XP150 (model # 150S) it would have had the high output 35 amp charging system. This 35 amp charging system puts out a lot of current. So, depending on which 150 model you have will also be part of the decision on whether you need an on-board charger or not.
