A deeper dive into Lithium batteries

[Raycaster]

BillM, you may be right(probably) and my electrical math rusty but won't a 24V 100ah be equal to 2 @12v 100ah in series?

 

 

[BassMan11]

17 hours ago, Raycaster said:

This is a great topic with content.

Just looking at this also as Im farting around with good/bad batteries.

Are there disadvantages of just going to a 24v battery? Charger?

Pros - Space and a little weight are some of the saving you would get with running a 24V battery. Another plus is the batteries not getting out of sync which can happen when you run 2 12 volts in series. That won't happen with a 24V.  There is only 1 BMS to deal with as well. Charging connectivity is very simple for whichever onboard charger you use. 

Cons - No other use for the battery... just dedicated trolling motor. Chargers are a bit more expensive and you have less brand options types. You will need 2 chargers for the boat 1 for trolling motor and a 12 volt for cranking or house battery. 

I am sure there are more on both sides... but just a couple off the top of my head.

BM

 

 

[BillM]

10 hours ago, Raycaster said:

BillM, you may be right(probably) and my electrical math rusty but won't a 24V 100ah be equal to 2 @12v 100ah in series?

 

 

Nope, I think I'm wrong   Voltage increases, capacity doesn't.    I blame this on not fishing enough this season  

[Terry]

I find 2 12 volt batteries  are easier to store the one big 24 volt and batteries so crap out 

if the 24 volt battery craps out you buy a new one ,expensive 

if a 12 volt battery dies you replace the one that crapped out and save half the money

but that’s just me 

Edited November 30 by Terry

[BassMan11]

58 minutes ago, Terry said:

I find 2 1 volt batteries  are easier to store the one big 24 volt and batteries so crap out 

if the 24 volt battery craps out you buy a new one ,expensive 

if a 12 volt battery dies you replace the one that crapped out and save half the money

but that’s just me 

Also.... In case of an emergency. You could pull the batteries out of your boat and run them with an inverter to power all sorts of things. Fridge, Freezer, even furnace for a short period of time. When moving into Lithium I went it with a "what else can I use these things for". Still 98% of the time they will just be for the trolling motor... but in a pinch.... I could have power anywhere. 

[QuiverCat]

On 6/26/2024 at 12:02 PM, Terry said:

I find 2 1 volt batteries  are easier to store the one big 24 volt and batteries so crap out 

if the 24 volt battery craps out you buy a new one ,expensive 

if a 12 volt battery dies you replace the one that crapped out and save half the money

but that’s just me 

Mostly agree but to be fair, at least in regards to LiFePO4 batteries (even the "cheap ones") that all have no-question asked warranties that are typically good for 5 to upwards of 15 years. I do know that some of the cheaper LiFePO4 batteries also have issues with being wired in series. The BMS on them don't like that.

Edited July 7 by QuiverCat

[CrowMan]

Just a heads up on a good deal. TRU Off Grid has AOLithium 12v 100amp LiFeP04 batteries for sale at $249. These are full featured batteries with BMS, cold weather cut off protection, and Bluetooth so you can monitor from your phone. 8 year over the counter warranty where you deal directly with the retailer above. First 5 years 100%, balance pro-rated.

I already have 2 of this brand for the past 2 years and they've performed flawlessly. Just picked up another one today for my smaller boat. Nice to deal with an independant Ontario small business, rather than Amazon. Contact Jack at 905-299-7841. Pick up in Milton.

[glen]

That has to be getting close to the price of a lead acid battery. 
 

[AKRISONER]

13 hours ago, glen said:

That has to be getting close to the price of a lead acid battery. 
 

i was able to get a 36v 100AH Heated, Bluetooth, waterproof lithium for $1200 last week. Canadian tire is selling their AGM's for $440...

Lithium prices have collapsed. I spoke with a friend who is an electrical engineer that specializes in energy storage and I grilled him on capacity, output, size, weight and his recommendation was that going lithium was a total no brainer. Encouraged me strongly to make the switch.

Heres perhaps the biggest stat change of all. Having two Group  100AH Group 31 AGM's in series to make 24volts in my boat...67lbs per battery for a total of 134lbs

I am now upgrading to a 36v 100AH system (equivalent of 3 batteries) total weight...74lbs

Ill also add, im on year 3 with my AGM's and they are pooched already. I'm too hard on trolling motor batteries. My other 2 in the boat are still fine, but 10 hour days fishing on the great lakes and close to 400hours+ pushing them every year just cooks them too fast. Apparently lithium will hold up to this a lot better as well.

They still charge up and have juice for the first few hours, but they cant get me through a long day fishing in 50km wind anymore and that doesn't cut it in a tournament day.

its a big big ol battery...just need to figure out where to fit it in the bilge area 🤪

Edited December 2 by AKRISONER

[CrowMan]

9 minutes ago, AKRISONER said:

i was able to get a 36v 100AH Heated, Bluetooth, waterproof lithium for $1200 last week. Canadian tire is selling their AGM's for $440...

Lithium prices have collapsed. I spoke with a friend who is an electrical engineer that specializes in energy storage and I grilled him on capacity, output, size, weight and his recommendation was that going lithium was a total no brainer. Encouraged me strongly to make the switch.

Heres perhaps the biggest stat change of all. Having two Group  100AH Group 31 AGM's in series to make 24volts in my boat...67lbs per battery for a total of 134lbs

I am now upgrading to a 36v 100AH system (equivalent of 3 batteries) total weight...74lbs

Ill also add, im on year 3 with my AGM's and they are pooched already. I'm too hard on trolling motor batteries. My other 2 in the boat are still fine, but 10 hour days fishing on the great lakes and close to 400hours+ pushing them every year just cooks them too fast. Apparently lithium will hold up to this a lot better as well.

They still charge up and have juice for the first few hours, but they cant get me through a long day fishing in 50km wind anymore and that doesn't cut it in a tournament day.

its a big big ol battery...just need to figure out where to fit it in the bilge area 🤪

As you say, lithium has become a "no brainer" for any deep cycle application. Frankly, I don't understand why the big box retailers like Canadian Tire and Costco haven't jumped on the bandwagon ? I would think we should be seeing a Nautilus or Kirkland brand lithium by now.

Just curious what the rationale was going one 36v vs 3 x 12v ?

[AKRISONER]

2 hours ago, CrowMan said:

As you say, lithium has become a "no brainer" for any deep cycle application. Frankly, I don't understand why the big box retailers like Canadian Tire and Costco haven't jumped on the bandwagon ? I would think we should be seeing a Nautilus or Kirkland brand lithium by now.

Just curious what the rationale was going one 36v vs 3 x 12v ?

Absolutely agree...youd think there would be a nautilus or discount kirkland lithium by now.

Pretty straight forward on this one...1. Cost and 2. Space 3. Charger implications

I got word of a deal from a friend and was able to get a Roypow (now Epoch) 36v 100Ah premium line self heating, bluetooth, waterproof battery for $899 US

Im seeing the same battery now listed for $1499us...only catch was that it would only ship within the CONUS...so I am going to have to drive down to Michigan before next season and bring it over the border. Im lucky my brother runs a warehouse in Michigan so it is there until I can get down there to get it.

2. Space 3 batteries is a larger footprint than 1, its a big bloody battery though, its 20 inches long and 10 inches wide.

3. Finally, with my current mix of AGM's for starting and electronics (I will eventually switch these to lithium when the time comes) Its easier for me to just grab a 36v charger to add into the boat to do my trolling motor batteries for now instead of needing to buy a 5 bank lithium capable charger. Eventually when I replace my starting and electronics batteries, I will simply buy a 2 bank lithium charger and be done with it.

 

[floater]

I just bought a Power Queen 50 aH for the trolling motor. It's allot smaller than I thought it would be and only 11 pounds. Looking forward to trying it out next season. I will hook the Lowrance HDS 5 into it as well and see how long it lasts. Supposed to charge in two hours.

[AKRISONER]

On 12/5/2024 at 6:59 AM, floater said:

I just bought a Power Queen 50 aH for the trolling motor. It's allot smaller than I thought it would be and only 11 pounds. Looking forward to trying it out next season. I will hook the Lowrance HDS 5 into it as well and see how long it lasts. Supposed to charge in two hours.

Don’t run graphs on the same battery as your trolling motor, it will give you interference issues. You’d be better off getting a 10ah or 20ah lithium for the sonar.

[floater]

Ah crap. Ok I will hook graph onto starting battery. Thanks