Batter Voltage After Fishing

[tnriverhammer]

I am currently running a group 31 odyssey cranking battery that I just got in February. I have two lowrance hds 12's one on the console and one up front, active target, a helix 12 on the console, and a helix 10 up front that the battery is powering along with all the other normal things that are attached to the cranking battery including poles. I fished a tournament this weekend had both livewells running and by the end of the day the voltage on my front HDS 12 got down to 11.2. I turn the console graphs on standby when I am not in the drivers seat and I didnt notice any issues with the voltage being that low, but I was just curious what everyone else experiences as far as voltage goes after a day of fishing. I really dont want to go lithium and I've been considering adding a 2nd 31 group odyssey in parallel to my other one. Has anyone done this and if so what kind of voltage are you seeing at the end of the fishing day?

[bobcoy]

Do you charge that battery every time you use it? If not do you monitor it? I have a 2150 and works great as a starter boat battery(pumps,livewell, lights etc.) I need an electronics battery to keep from draining the starter battery. Unless you are running the big motor quite often you will end the day way less than full charge. It needs charging. JMO Bob

[tnriverhammer]

Do you charge that battery every time you use it? If not do you monitor it? I have a 2150 and works great as a starter boat battery(pumps,livewell, lights etc.) I need an electronics battery to keep from draining the starter battery. Unless you are running the big motor quite often you will end the day way less than full charge. It needs charging. JMO Bob

It is plugged up charging every time the boat isnt being used. I dont expect it to be fully charged by the end of the day by any means. Just curious what others were seeing and what those who have batteries in parallel are seeing as far as voltage

[catdude28]

You will get a more accurate reading if you measure with a voltmeter at the battery instead of relying on the graph.

[CatFan]

The reading on the graph is not accurate. Measure at the battery terminals with a meter

[haus9393]

I am currently running a group 31 odyssey cranking battery that I just got in February. I have two lowrance hds 12's one on the console and one up front, active target, a helix 12 on the console, and a helix 10 up front that the battery is powering along with all the other normal things that are attached to the cranking battery including poles. I fished a tournament this weekend had both livewells running and by the end of the day the voltage on my front HDS 12 got down to 11.2. I turn the console graphs on standby when I am not in the drivers seat and I didnt notice any issues with the voltage being that low, but I was just curious what everyone else experiences as far as voltage goes after a day of fishing. I really dont want to go lithium and I've been considering adding a 2nd 31 group odyssey in parallel to my other one. Has anyone done this and if so what kind of voltage are you seeing at the end of the fishing day?

This is a very large electronics draw for just 1 big battery to handle. Typically once you get over 3 12” graphs it gets hard for a single group 31 with 100ah to handle a 10 hour day. I would suggest looking to add a 2nd agm in parallel to double your reserve capacity and double the length of run time. I can tell you from years of experience you are about to be in a bad place next year if you keep drawing your battery down that low. Each time the battery goes below 12.0v it shortens the life. Seems like after 100 cycles the battery is half the battery it was at new. So more than likely by mid season next year you will be trying to break out the jumper pack towards the end of the day with a dead cranker. A few years ago when I went from 3 12” units to 4 graphs and 360 I started having low voltage and after a year of replacing batteries and wasting probably $800 I ended up hooking 2 in parallel and made a world of difference with no more voltage issues.

[bayoufellow]

I had been using your same battery for years without difficulty until I started adding on the extras on the bow. I was having the same issues you described very low voltage. Long story short ended up switching to a 125 amp lithium. Initially, I thought I would be adding a 5th battery(the lithium being the 5th) just for the bow, but this battery was good to use with my outboard(from both starting and the outboard charging system compatibility with the lithium) and battery charger(same one used for the Odyssey AGM's).
Usable amps for the Odyssey was 50, and the 125amp lithium I have 100 amps of usable power. No issues at all now and I have yet to drop below 12.7 on an all day trip. At this rate I could go 2 days without charging and part of a third day

[tnriverhammer]

I had been using your same battery for years without difficulty until I started adding on the extras on the bow. I was having the same issues you described very low voltage. Long story short ended up switching to a 125 amp lithium. Initially, I thought I would be adding a 5th battery(the lithium being the 5th) just for the bow, but this battery was good to use with my outboard(from both starting and the outboard charging system compatibility with the lithium) and battery charger(same one used for the Odyssey AGM's).
Usable amps for the Odyssey was 50, and the 125amp lithium I have 100 amps of usable power. No issues at all now and I have yet to drop below 12.7 on an all day trip. At this rate I could go 2 days without charging and part of a third day

Which lithium did you go with? I am thinking about making the switch

[CatFan]

I had been using your same battery for years without difficulty until I started adding on the extras on the bow. I was having the same issues you described very low voltage. Long story short ended up switching to a 125 amp lithium. Initially, I thought I would be adding a 5th battery(the lithium being the 5th) just for the bow, but this battery was good to use with my outboard(from both starting and the outboard charging system compatibility with the lithium) and battery charger(same one used for the Odyssey AGM's).
Usable amps for the Odyssey was 50, and the 125amp lithium I have 100 amps of usable power. No issues at all now and I have yet to drop below 12.7 on an all day trip. At this rate I could go 2 days without charging and part of a third day

The idea that you can only use half the capacity of a lead acid battery is a complete myth. The characteristics that gave rise to the myth apply nearly the same way to lithium batteries as well.

[haus9393]

The idea that you can only use half the capacity of a lead acid battery is a complete myth.

Yea not sure how it started but unfortunately this statement has really caught on with the bbc members and it probably isn’t going away.

[CatFan]

Yea not sure how it started but unfortunately this statement has really caught on with the bbc members and it probably isn’t going away.

I believe it started from the designers rule of thumb that for best economics, you should size your battery bank for an average 50% depth of discharge between charges. That takes into account power use, battery size and charging frequency. The idea is that bigger batteries cost more over time because of initial cost and their service life due to simple age related degradation is no longer than a smaller battery. Smaller batteries need more frequent replacement. Goldilocks is at that average 50% discharge.

But the message shouldn’t be not to discharge below 50%. The message should be if you regularly need to discharge below 50% you chose a battery or battery bank that is too small and need to get a bigger battery next time. The concept is the same for lithium-ion, but the numbers may not be the same.

Make no mistake though, regularly deeply discharging a lithium-ion battery shortens its service life compared to shallower discharges. Roughly speaking, the service life at average 80% DoD is somewhere between 1/4 and 1/3 of the service life at average 20% DoD.

[bayoufellow]

I went with a LithiumHub Ionic lithium battery. There are probably several that would have fit my needs, but I got the answers I needed quickly from this company. I purchased the 12 volt 125 amp deep cycle model. Check with them for sure for your needs and your present system to see what will work.
My reasons for purchasing this battery: (Information obtained from the battery company)
1) I could use it to start my outboard.
2) This outboards charging system is compatible with the above battery.
3) My model of the Pro Mariner 4 bank charger would work with the above battery.

In addition the above, the Ionic battery fit in the same space and battery bracket that held the Odyssey 2150 previously.

No complaints with my Odyssey batteries this is my second set(still have three on the trolling motor, and three from the first set are still in some tractors and going strong). I just needed more power to get through a day of fishing without concern about getting home at the end of the day.

Hope this helps.

[tnriverhammer]

I went with a LithiumHub Ionic lithium battery. There are probably several that would have fit my needs, but I got the answers I needed quickly from this company. I purchased the 12 volt 125 amp deep cycle model. Check with them for sure for your needs and your present system to see what will work.
My reasons for purchasing this battery: (Information obtained from the battery company)
1) I could use it to start my outboard.
2) This outboards charging system is compatible with the above battery.
3) My model of the Pro Mariner 4 bank charger would work with the above battery.

In addition the above, the Ionic battery fit in the same space and battery bracket that held the Odyssey 2150 previously.

No complaints with my Odyssey batteries this is my second set(still have three on the trolling motor, and three from the first set are still in some tractors and going strong). I just needed more power to get through a day of fishing without concern about getting home at the end of the day.

Hope this helps.

I ended up buying this same battery yesterday from Drewcraft. I am hoping it solves my needs! All the reviews are great. I appreciate the feedback!

[Ohio Archer]

I really wish I had the time to devote to running any of my batteries down to the point they failed. I'm lucky to get out 2 times a month for 6 hours. Had that happen once, though, on an older wet cell battery that lost a cell. But I digress and, thusly, end my hijack...

[CJ1]

I believe it started from the designers rule of thumb that for best economics, you should size your battery bank for an average 50% depth of discharge between charges. That takes into account power use, battery size and charging frequency. The idea is that bigger batteries cost more over time because of initial cost and their service life due to simple age related degradation is no longer than a smaller battery. Smaller batteries need more frequent replacement. Goldilocks is at that average 50% discharge.

But the message shouldn’t be not to discharge below 50%. The message should be if you regularly need to discharge below 50% you chose a battery or battery bank that is too small and need to get a bigger battery next time. The concept is the same for lithium-ion, but the numbers may not be the same.

Make no mistake though, regularly deeply discharging a lithium-ion battery shortens its service life compared to shallower discharges. Roughly speaking, the service life at average 80% DoD is somewhere between 1/4 and 1/3 of the service life at average 20% DoD.

Very well said. I wish I had more experience with Lithium but they just do not work for my off grid applications because of cold. CJ

[lpugh]

Here is what most are missing about a lithium advantage. A SLA or AGM battery has far more electrical resistance to excepting a charge. When first starting up at cruse speed you may have up to 30 amps of current going into the battery, this rapidly drop off to less than 12 amps due to the resistance of the battery. A lithium can and will except the full 30 amps for quite some time,
You far greater charge recovery rate with a lithium battery. I have verified this by watching the bluetooth app on my phone, watched a 11 % loss fully recovered in a 12-mile run
At best an AGM battery would get maybe a 4% improvement

[LithiumBattMan]

good batteries have bluetooth, such as Ionic, Seaquestbattery, Monster, etc.