Deep Cycle Batteries FAQ
If you have never used a deep cycle battery and a trolling motor there is a learning curve. I am not an expert but I have gained a lot of knowledge using the Ultraskiff for 3 years now and I will try my best to share with you what I know so far.
The most frequently asked question we get is: How long will a motor run on a battery?
That is very subjective to a large amount of factors. The primary factor is Amp Draw or in simple terms "How often you run the motor". You don't run the motor continuously the entire day, so there are all these sub-factors that determine your rate of amp draw and run time. Lets start by explaining amp-draw then go into the sub factors. I will address all the questions about batteries the best I can in this one presentation with trolling motors at the end.
What speed you set the throttle determines the Amp draw. A 55 Lb thrust motor will pull 5 amps at full 100% throttle, at that rate of speed the motor will run for 2 to 3 hours depending on your battery size. If you set the motor at 75% speed it will only draw around 2.5 amps. So the amount of amp draw drops fast when you take the throttle off of full speed. Half 50% throttle can draw as little as .5 to 1 amp. This is a very good thing because as long as you try and stay off of 100% thrust unless you absolutely have to your available run time on a single charge can be increased dramatically.
1. Total Weight
Your total weight determines how many amps the motor will have to pull to travel a particular distance. The more weight in the boat, the less run time you have on a single charge.
Your fishing or hunting style has a lot to do with your available time on the water, if you are anchoring up from spot to spot you will be motoring much less if you were constantly motoring around all day and you can accurately predict your run time based on your total distance traveled to each spot along your route through-out your day. For instance when I am Bass Fishing I generally do not anchor, especially if I am using the Ultraskiff R.B.C.'s. SO I am conituaously running the motor between 25% and 100% the entire day. But I get between 4 and six hours of fishing and motoring of a single battery depending on wind speed. WHich brings us to the next sub factor.
Wind and current play a part in determining your run time as well. The more you fight the wind or current the more amps you will use to get to a certain destination. Wind and current behind you can actually help save battery life, so it can go both ways and even out in some cases.
4. Battery Health
Battery health is very important. Keeping your terminals and the connections coming from your motor clean is a must. Using a wire brush to clean your terminals and all metal to metal connections periodically will help the efficiency of your amp draw and power use. Including the metal connectors coming from your trolling motor, do not neglect them, keep them shiny and clean. Trac trolling motor Plugs are a great option, Click here to Watch a Video on how to use them. When charging your battery it is best to not charge past a rate of 10 amps, a slower charge increases the life span of your battery. I usually charge overnight at 7-8 amps. Battery Chargers automatically shut off and switch to a trickle charge maintainer after the battery is fully charged. It is also good to re-charge a battery as soon as possible after discharging, leaving a battery depleted for days will only hurt the overall long term health of the battery. Do you need a Fuse or Battery Box with your battery? No, I have never used one and never had an issue, I just clamp the motor directly to the battery.
Deep Cycle Battery Types
This is my favorite choice, they are inexpensive and as such should be replaced every couple years depending on use. I find that it is more effective to buy a fresh battery when needed then initially investing in a battery with a longer total cycle life span that costs 3 times the amount. The only draw back is you cannot tip them over for a prolonged period or the acid and fluid will begin to leak and then your battery is ruined. These batteries are very water resistant, they can be rained on or sit in water all way up to the top of the battery with no problems at all, the only thing you cant do is completely submerge them in water because the caps on the top of the battery are not sealed. So do not drop them in the lake. Always save the receipt from your battery purchase and if you ever suspect a problem just return it and exchange it for a new one. I use the heck out of mine fishing twice a week all year long on the same battery and usually exchange it before the one year warranty is up. But in general with low-moderate use you should get 2-3 years out of one.
Gel / AGM
These sealed batteries are nice because the acid cannot spill out from the battery if it is tipped over. They also have a longer life span (cycle life) and can last 3-5 years. Negatives are that they are much more expensive and the risk of your damaging your battery from improper handling still exists. The way I look at it is I would rather spend $75 on a fresh battery every one to 2 years that has a fresh warranty and fresh core then spend $250 on a battery that also has risks of malfunction down the line.
I have done alot of testing on the lithiums this year and the results were not as great as I wanted. The positives are that they are Lightweight and keep a consistent level of voltage throughout a cycle until they die out. The negatives are that they are much pricier then a normal acid based deep cycle, WHile one small 15 Lb 50 AH Lithium may have the same run time as a DC 24, all your really saving is about 25 Lbs at a cost comparrison of $75 to $600. They are less water resistant then normal acid based deep cycles and when they die out they do not steadily slow down over a period of time like normal acid based deep cycles do, instead they just abruptly stop running which could leave you stranded. Which is why whne I use them I like to use them as a back up to a normal acid based deep cycle, since I know I have normal deep cycle that will give me plenty of notice that it is approaching its end and thus giving me time to get back to my launch point. Which brings us to our next topic: Charge Meter
Battery Charge Meter
I have found a charge meter is not very essential. Deep cycles slowly begin to die out when they dip below 12V. Then they could run for hours after they get below 12V until you are actually stranded. The battery meters that come with trolling motors are not a reliable source of information because as soon as the battery dips below 12 V it says your battery is dead, I have had alot of people claim they only get 4 hours of use before the motor says the battery is dead but in actuality they have not even began to touch their actual reserve capacity of the battery yet. The thing is I always notice the drop in voltage and loss of speed when Im out there and I can tell when its time to head back into port or switch to a back up battery. Which brings us to our next topic: Back up batteries.
Back up Batteries
For long 6-12 hours trips I like to bring a back up battery. I generally like to bring a small battery as a back up since it keeps the weight of the boat down but a large one is fine as well in the side or front storage compartment. I use the side compartment and so I can run the motor cables directly to the battery through the door wire holes when I need to switch. My favorite back up batteries are a DC-24 at 40 Lbs or a 50 AH lithium Ion at 15 Lbs. You can use any battery size as a backup but I like to bring something small like a DC 24, since it is more then enough power for a full day combined with your primary battery and its less weight in the boat. Which brings us to our next topic: Battery Sizes
Battery sizes and My Favorites
Every size of battery has been my favorite at one point but currently I like the smaller DC24 or DC 27 as my primary battery. 2 years ago I was into DC 29's and last year I was into the DC 31 and preached to everyone how great it was that I could take longer trips off of one battery. Then I discovered I feel much better bringing 2 smaller batteries then one giant battery because of what I call the "line in the sand". It is hard to gauge exactly the half way point of a batteries life, especially on the larger batteries because of the size of their reserve capacity, so you while you will get much longer run time after it dips below 12 V, your still operating below 12 V and at that point whatever battery meter you have on your motor reads dead when you actually have 2-3 hours of use left. So rather then bringing one huge 65 LB DC-31, I would rather take 2 - 40 LB DC 24's. I have a lot more power and run time and if one battery dies I know exactly how much is left (an entire battery) and when I switch to that new battery I go back up and start at 13 V again. A no brainier for a difference of 15 Lbs. Plus, my days are usually half day (4-6 hours) and full days (6-12 hours), I usually don't fish for more then 5 hours so on most trips I only need one DC 24 or one DC 27. And even on Full days I quite often don't even get to the back up battery.
Estimated Battery Weights:
DC24 - 40 Lbs
DC27 - 47 Lbs
DC 29 - 60 LBs
DC31 - 65 Lbs
Trolling Motors FAQ
Q: What size motor do I get:
A: I recommend either a 50 LB or a 55 LB 12 V motor for an adult. You can use any size you want actually, especially if you live on a small lake or pond it doesnt matter. But if your fishing bigger waters and are going to cover more range the added thrust could be beneficial when it comes to wind/current.
Q: What size shaft length do I get?
A: With our 17" transom you can go 30", 36" or 42". If I had to choose one size I would go with the 42" shaft. Only because if you want to steer while standing the 42" will allow you to keep it up at your waist and you wont have to bend much down to touch it. I use the 36" while standing with no problems, I just have to reach a little bit, but if that's a concern go with the 42".
Q: Do I get a Manual or Variable Thrust?
A: Variable all the way. No question about it. So much easier to control and handle while also increasing your available run time.
Q: Can I use a foot control trolling motor?
A: Yes and No, I own a 55 LB Bull Dog transom foot control system but foot controls and 6 ft light weight boats do not go together well at all. The first reason is that it conflicts with the reason for owning a round boat: You can face, stand or sit in any direction you want to and have control of the boat. At first glance I guess its hard to notice that the tiller is inches away from either hand at all times but it is. That is the biggest advantage, that I can nudge, touch, turn and shift gear with either hand while facing any direction on the 360 Degree seating clock, it really comes in handy. I suppose its something you have to experience to understand. You use the motor a lot, so having to turn in your chair and face a certain direction each time you want to turn the boat or control the motor gets really tiresome. The steering is already sensitive on a boat this short and light and when you add the sensitivity of the foot control it is a perfect storm of frustration.
Q: Can you use the boat with a more powerful 24V transom mounted trolling motor?
A: Yes, I have recently tested an 86 lb. thrust transom mounted trolling motor, worked really well. In my opinion I would rather have a 12V 55lb thrust motor. The overall difference in speed is not enough to change my opinion that I would rather just use a 55 Lb Thrust. There is a limit as to how fast you can go in a displacement hull like this because of how short the waterline length is.
Q: Can I use a gas powered motor?
A: Yes you can but it is coast-guard rated for 2.0 hp or lower. I made sure I designed a 17" transom so you can use a short shaft outboard but a gas motor is very jerky and the torque from the gas motor turns/spins at a high rate of speed. Unfortunately, the craft is just too short and wide to be a planning hull, it navigates like a barge therefore your top speed is limited to about 4 mph. The only time you can efficiently convert your power into speed is when you have an even waterline from bow to stern. With a trolling motor the skiff always moves smooth and at an even water line. A standard deep cycle battery powered transom mounted trolling motor is the best and safest choice for the Ultraskiff 360 in our opinion.
In the video below we give you some tips on keeping ahealthy connection and show you how to install Trac trolling motor plugs to your motors and batteries.