Generally speaking here recognizing it is battery-specific so let’s assume stock dual battery setup for 2018 242Xe. If I fully charge/condition both batteries with a marinerpro then run the stereo and connext screen...in float mode no engines...are we talking couple hours, half day, all day as far as expectations go as to how long before low house battery?
my batteries have stickers on them of 9/17 and 2/18. Is this the production date for each?
Finally - replacement recommendations if I go that route?
thanks!
I suspect that the dates you listed are the manufacturing dates. Assuming these are flooded lead acid batteries of the group 27 size, are in good condition and were properly maintained, they are probably at half of their service life.
Assuming again that the above statement is accurate, and with the loading you described with a stock stereo, I’d say you could go 8 hours before the house battery would start to get low. The connext screen with it’s micro processor and LCD screen are pretty thrifty with milliamps.
@Canuckjetboater makes some great points about batteries!
What comes into play when deciding on batteries is cost as well as performance. For ability to discharge deeply and charge quickly, no maintenance, the Lithium ion type of batteries are great, not to mention their 60% less weight, their cost is the main downside. If you decide to go the lithium ion route, I’d give Yamaha corporate a call and verify this type of battery is compatible with your boats charging system. I had talked with them once about the lithium batteries, and all I remember from that conversation was that the lithium ion batteries had not worked out well with Yamaha outboard engines-these engines have a more traditional style of alternator/ automotive style which is different from the charging system in our boats. It has to do with how quickly the lithium ion batteries charge / charge rate, which is much higher than traditional lead acid batteries. The outboard / automotive style of alternator uses a regulator that varies the magnetic field strength to regulate the amount of voltage / charge output. Whereas our charging systems have a fixed magnetic field and the regulator shunts excess voltage/charge to ground.
I’m a big fan of Trojan batteries, talked to their tech line one day about their lithium batteries and the aforementioned issue of charge rate. The Trojan tech told me their line of lithium ion battery has a microprocessor based switch that will disconnect the battery for a short period of time if the charge or discharge rate is too high. I would imagine most lithium ion batteries have that type of tech, but it’s worth investigating if you decide to go that route.
I have lithium ion batteries in my dirt bikes, but that is the only place I have them. These batteries made by antigravity were / are a huge improvement (50%) over the lead acid batteries that came in the bike in terms of cold cranking amps and amp hours. I have only experienced the only performance down side of lithium ion batteries a few times which is in temperatures of 32° or less they have dramatically reduced performance initially. Hit the start button when it’s that cold and the battery acts as if very low, wait 60 seconds and try it again and the performance is greater, wait another 60 seconds and hit the button the third time and the battery is at full output.
The batteries in my boat, start, house, and 36 volt trolling bank are all flooded lead acid group 27 size. These batteries are all dealership branded batteries and I do not know who manufactured them and so far they are working great. I have considered replacing the house and trolling motor bank batteries with lithium ion when they need to be replaced, however, that $1000 a piece price tag is daunting, I could replace a flooded lead acid battery I have 5 times for the cost of one lithium ion battery. For me it comes down to performance, and so far the lead acid batteries are meeting my needs. The 60% weight savings (204#) of the lithium ion batteries would be nice, but I’d never notice it, except when removing / replacing them.
After floating for 6-8 hours with the connext screen off, my fish finder running, the stock stereo running, the live well aerator running intermittently, as well as the live well fill pump running occasionally, the house battery drops into the 11.4 volt range. Once the connext screen shows an alarm for low house battery voltage I’ll start the engines and troll with them for a while until I see the house battery voltage recover to 14 volts.
Hopefully that missive gives you a bit of idea about battery life and battery choices.
Here is a link for you to consider.
Measuring A Lead Acid Battery State of Charge by Compass Marine How To
