Lithium battery - worth the expense?

[senkosam]

A bud just boat a lightweight Li battery for 350 bucks. Anyone buy one and was it worth it?

Claimed advantages:
1. A lithium battery can keep your trolling motor at the same speed for almost twice as long as lead-acid batteries of the same rated capacity.

2. Most lithium batteries can be discharged down to 10-20% SoC (State of Charge). If you regularly discharge a lead-acid battery below 50%, it will deteriorate faster, and you will have to replace it sooner.

3. You get the same rated capacity even when discharging them very fast. A lead acid battery whose amp hours is based on discharge speed, will have less power sooner the more amps drawn by the t.m.

4. Good lithium batteries can handle 3000-5000 charge/discharge cycles. Good lead-acid batteries last only 200-300 cycles if discharged only to 50% of their rated capacity. However, if you regularly take them down to 20% of capacity, you will quickly damage the battery, which will have perhaps only around 30-50 cycles available with available capacity diminishing as well.

5. Lithium batteries don’t suffer from sulfation, which occurs in most lead-acid batteries. Sulfation is a buildup of lead sulfate crystals on lead-acid battery plates. It occurs whenever a battery is left without a full charge, and it is the main reason lead-acid batteries lose performance and fail. Sulfation is responsible for longer charging times, shorter run times and shorter battery life.

6. Lithium batteries typically weigh 60% less than marine lead-acid batteries and take less valuable space.

7. Lithium batteries can be charged with as much current as 100% of their Ah capacity, which means 3-5 times faster than lead-acid batteries. For a lead-acid battery, recommended charging current is 10-30% of the rated capacity. For example, you shouldn’t fast charge a 100Ah lead-acid battery with more than 30 Amps.

8. Lithium batteries typically weigh 60% less than marine lead-acid batteries and take less space.

 

[Ray Clark]

I'm not sure of your question. Are you asking if budget Lithium batteries match expectations of higher cost Lithium batteries, or if Lithium batteries meet the claims listed?

To be precise, I'll talk about my experience so far with the budget Lithium Iron Phosphate (LiFePO4) battery I bought last summer.

I bought a 100AH LiFePO4 battery last summer for my trolling motor and accessories. I like it so far; it has worked well. I paid about $350 for mine, though the same battery today now costs about $300 on Amazon.

There are quite a few YouTube vids about various budget brands. There are enough that some will point out problem areas while others review build quality and performance. One of the more complete reviews I have seen is Battery Review.

My battery is less than a year old so I can't talk to longevity.

My LiFePO4 battery is a Group 31 sized case, so I can't say it's "smaller" than a comparable battery.

My battery weighs 26 pounds. My Group 24 lead-acid starting battery weighs at least 35 pounds. Not an apples-to-apples comparison, but is indicative of significant weight savings.

I can't talk to "fast charging" times. My power charger puts out 5 Amps per bank, so a full charge on the 100AH battery takes 20 hours.

Happy with mine so far, so for me, it's worth it.

 

[sonny1]

Lithium batteries was the rave in the motorcycle world. Problem is they do not work well in cold weather. A lot of folks where getting stuck with a bike that would not start. Guess it would work for fishing.

 

[FuzzyGrub]

I have one to run the electronics. So far its been great. If it holds up to claims, I'll try LiPO4 for the trolling motor batteries when they need to be replaced. The weight savings will be a plus in a jet boat.

 

[MrGiggles]

Biggest advantages I see, less weight, and longevity. They've come down in price enough now that if it lasts twice as long as a lead acid, you're breaking even, which they should last 2-5 times longer so you're money ahead there. In boats that have 2-4 deep cycle batteries, there is a substantial weight savings to be had, which is a big benefit as well.

The bad, they require a special charger in most cases, and do not work well in cold weather. Given the application, cold weather may or may not be an issue.

I haven't invested in lithium trolling batteries yet, but do have a 12ah lithium to run my bow electronics. My Noco charger seems to charge it just fine, overall I am happy with it.

 

[Ray Clark]

Biggest advantages I see, less weight, and longevity. They've come down in price enough now that if it lasts twice as long as a lead acid, you're breaking even, which they should last 2-5 times longer so you're money ahead there. In boats that have 2-4 deep cycle batteries, there is a substantial weight savings to be had, which is a big benefit as well.

The bad, they require a special charger in most cases, and do not work well in cold weather. Given the application, cold weather may or may not be an issue.

I haven't invested in lithium trolling batteries yet, but do have a 12ah lithium to run my bow electronics. My Noco charger seems to charge it just fine, overall I am happy with it.

My charger is a NOCO Genius 5X2; it has settings for battery type, including lithium. Many battery chargers have such a setting these days. But you do have to pay attention to make sure that the charger is "set right."

 

[senkosam]

Are you asking if budget Lithium batteries match expectations of higher cost Lithium batteries, or if Lithium batteries meet the claims listed?

Mostly to find anyone who uses a deep cycle Li battery and if they agree with the positives noted. I've never heard of a budget Li battery, but if it holds its charge better than lead batteries at mid-speed using the trolling motor, I might consider buying one for my light aluminum row boat. (Especially to save the back hauling it in and out of truck and boat!)

Thanks to all of you for help shooting me in the direction of a budget (?) Li.

 

[Ray Clark]

Both, Mr Clark and you've so magnificently! Thanks to of you for helping me decide that my next deep cycle battery will be a budget (?) Li.

My strongest recommendation would be to research some of those YouTube creators who are doing a decent job of really looking at battery quality and performance.

Pay particular attention to information about Battery Management Systems (BMS). Different brands have different BMS arrangements. Ability of the battery to handle the climate in your region is a good thing to know. For example: My battery will provide power down to -4F. However, attempting to charge the battery when the temp is below 32F will damage the battery. Some batteries have a BMS that will prevent charging when temps are outside charging limits. However, the BMS on my budget battery is not that sophisticated, so I have to be aware when the temperature is out of limits. My boat is stored indoors, but that storage building is not heated. I pull the battery in the winter and move it into the heated shop building where it sits on maintenance charge all winter.

In addition to the link in my earlier post above, another channel I've surfed to learn about LiFePO4 batteries is "DIY Solar Power with Will Prowse". Here's a link to playlists that might be worth your time: LiFePO4 batteries.

 

[FuzzyGrub]

FWIW: The first LiPO4 battery I purchased only had about half of the advertised AH. Here is the review: My Review

May hve been a fluke, didn't try a 2nd one of that brand.

I went with this one, and it tested fine: Better One

My advice is to test it before spending the time installing and going on the water. Also, make sure you can return the battery within 30days. Some you can't. And then have to go thru a PITA process and ship at your expense, to rectify.

 

[senkosam]

ECI Power 12V 20Ah Lithium LiFePO4 Deep Cycle Rechargeable Battery​

Is that the right size for my boat? - no gas motor is used.

 

[airshot]

The only issue I have is taking them down to 20%, sounds to low...in reality they have a builtin cutoff voltage. If the battery drops below a certain volt per cell they won't recover. Most lithium batteries today have this cutoff built in. Your warranty is void if you drop the voltage below the minimum!!! As always read the fine print carefully!!! Follow instructions to the T, no room for a woops on lithium batteries. They are great if you get a good one!

 

[FuzzyGrub]

ECI Power 12V 20Ah Lithium LiFePO4 Deep Cycle Rechargeable Battery​

Is that the right size for my boat? - no gas motor is used.

I use that just for my electronics. I thought it was worth mentioning the issue with the 1st one, when I re-read your post and saw that you were interested in the "value" brands. Its in the ammo can in the picture.

BTW: It has a max charger size of 10A. I read using a "fast" charger can shorten their life. I use a 5A Noco on this battery. I go two outings, then recharge. Fully charged in the AM.

 

[Ray Clark]

ECI Power 12V 20Ah Lithium LiFePO4 Deep Cycle Rechargeable Battery​

Is that the right size for my boat? - no gas motor is used.

What are you powering with that battery?

Just a small fish finder? If so, then it's probably good for a long day of fishing.

My Humminbird Helix draws .8 Amps. It could probably drain that battery with two 10 hour-long days of fishing.

If you're also running a trolling motor with that battery, then I think you'll find that a 20AH battery is pretty limiting.

My Minn Kota Powerdrive 55# thrust motor draws 50 Amps at full throttle. It would drain a 20AH battery in less than 25 minutes of continuous use, and that's with nothing else using any energy from the battery.

Edit to add: I'm not sure I could even safely hook up that 20AH battery to my Minn Kota. I don't think I should try to draw 50A from that smaller battery as damage may result.

It's all about how you plan to use that battery.

 

[senkosam]

I use a 55# thrust Minn Kota but usually use a steady discharge going from spot to spot and when returning back to the dock to go home. Otherwise, my trolling speeds vary between 1-3 speeds with me rowing silently into areas for shallow fish in weeds.

 

[FuzzyGrub]

It is an older Humminbird 999ci SI HD. It draws 1.1A. We leave it on all day, which ranges from 7-9 hours. I wouldn't think of using for a trolling motor. If/when I switch the trolling motor batteries, be looking for two, with a minimum of 100Ah each.

 

[LDUBS]

Here is a link to a thread from a couple of years ago that might be useful:

Pondering trolling motor battery selection

 

[Skunked again]

Following this question/issue. Mainly for reduced weight. Currently have two 27 series lead acid. That’s a considerable amount of extra weight, in a 14’ v - bottom!

Good information in this thread!

 

[Still Afloat]

LiFe PO4, Lithium Iron Phoshate batteries are everything that they say they are. However, if you buy the cheapest one that you can find on eBay or Amazon it can be a real crapshoot. On the other hand some companies are charging twice what they should.

Comments about lower capacity and charging issues in cold weather are true but, some batteries have internal heaters to compensate. Keep in mind that most Lithium batteries are not cranking batteries. Also, lithium batteries will not fully charge with AGM or other lead acid chargers. You will need to purchase dedicated chargers.

I’ve run a 60Ah LiFe battery to power an electric kayak and smaller fishing boat trolling motors for about 12 years and it’s still running strong. The prices now are about 1/3 of what they were when I purchased it.

Recommendations
LiFe (deep cycle): LiTime
Lithium Cranking: Noco
Charging systems: Noco

 

[senkosam]

From all that, no way am I going Li even for my 12' jon boat with 2.5 hp 4-stroke!
Guess I'll be buying a new Pb acid battery that I'll recharge with my simple auto-charger.

 

[Still Afloat]

You can always reconsider lithium technology when that Pb battery won’t hold a charge in three years or so. Personally, I will never go back to Pb for marine applications.