OK here is some info for you on how long a battery will last on the subject of reserve time and other stuff. Reserve time is figured at 70 f. with a NEW and FULLY charged battery and how long it will last at a fixed 25 amp draw without taking the battery below 10 1/2 v. In batteries you get what you pay for. Figure you amp drain and divide that into your reserve time and it will give you how long your battery will last ON AVERAGE. Second, carry some oars with you. When you let your battery sit in the winter, figure it will loose on average 1/2 of 1% per day just sitting. The old adage that you have to set a battery on wood to keep it from discharging is just that an old adage. What will cause your battery to discharge faster is if it has a lot of dirt or moisture on top of it, that dirt/moisture carries voltage...take a volt meter and put it on top of a battery that is charged and has dust/moisture on it. Measure the voltage without touching the posts. If it is bad enough it will have voltage and it is going.straight to ground. Charging time, pretty easy ....if you are charging at 1 amp a 105 amp hour battery will take you 105 hours to completely charge from a fully dishcarged battery, that is below 10.5 volts and not sulfated or 1 hour charge time for every amp hour rating. You can add liquid to almost all battery's, there is usually a removable cap below that sticker on top. Do not top off your battery above the chimney, that piece of plastic hanging down inside the cell and either use battery acid or DISTILLED water. DO NOT USE TAP WATER as it has chemicals in it that will shorten your battery life. What you take out your must return, think of your battery as a bucket of water, to keep it full you have to fill it. A fully charged battery is about 13.5 volts or a little better depending on your battery. A battery with 12 v. in it is almost MT. There is more but this is the basics of it, I will back this up with the information that I worked in a battery warehouse/sales store for 3 years and that was all I did was battery's Battery's have changed but the basics is still the same.
Just how to bum rides in boats. The batteries will last 4 or 5 hours on a charge. I have an 80 lb. thrust I use on my DB. If the batteries die your paddling never had that problem. I use mine mostly for crabbing in the bays, as a matter of fact going tomorrow. It does take some time to recharge them though.
