Ok, so I finally decided to do a review on some of the smart battery chargers I have owned. This should help provide some guidance on the myriad of choices out there. I will list the charger, then give a brief description of what it is supposed to do, and what it actually does in the real world. I will also tell what type of connector is used for permanent wiring and accessories. All chargers come with battery clips and some form of weatherproof permanent wiring harness (to be attached directly to the battery). In order to keep this thing at a reasonable length, I will not go onto great depths on each and every charge mode. For more information, please contact me or visit each manufactures websites.
First order though is some info on basic battery types.
Flooded/Wet Cell- This is your standard type of battery. You have lead plates submersed in a sulfuric acid solution. You can have various types such as maintenance free, filler caps, starting, deep cycle, or marine duty, which is a cross between starting a deep cycle. The difference between deep cycle and starting is the design of the lead plates. In a starting battery you need maximum power for a short burst of time, so the lead plates have more of a 3D design. Think of a sponge versus a solid lead plate. This provides more surface area for more instant current draw. It also has a down side, all of those spaces in the plate can plug up with sulfur if the battery is drained too low. This sulfurization slows down the chemical reaction and reduces power. By contrast a deep cycle battery can withstand multiple deep discharges and still retain capacity. The more solid lead plates prevent sulfurization, or enable a charge to break up any accumulated sulfur. Deep cycle batteries trade reduced starting power for the ability to withstand deep discharges.
VRLA (Valve Regulated Lead Acid)- VRLA is a catchall for most forms of sealed batteries. Valves control the release of any gasses produced during the charge/discharge cycles. This provides, under normal circumstances, a recycling of the water that is released during the chemical reaction is recycled to the cells, so you never have to add water. If the battery is charged to fast, the valves will release any gasses to prevent a pressure build up. This will cause the electrolyte level to drop, since there is no way to add water, the battery will slowly die. This is why charging rates are very important to battery life. VRLA batteries can also be called MF (maintenance free) and spill proof. VRLA batteries can also have multiple types of electrolyte (including flooded cell), which will be explained next.
GEL Batteries- Can also be called gel cell. In this type of battery, the electrolyte is in the form of a gel like substance. This allows for a smaller more compact battery. All gel batteries are maintenance free and have some form of valve regulation. Gel batteries have a reputation of failing suddenly. This is due to the gel in contact with the plates becomes “dry”, reducing the chemical reaction. Since they are sealed, no additional water can be added. Again, charging and discharge rates need to be watched to prolong battery life.
AGM- Absorbed Glass Mat or Advanced Glass Mat. These batteries have the electrolyte held by glass mats between the lead plates. This is an advancement of the gel batteries. AGM batteries are more long-lived and less susceptible to overcharge/discharged damage. AGM batteries do not have any liquid to spill, and even under severe overcharge conditions hydrogen emission is far below any other form of battery. The plates in AGM batteries are tightly packed and rigidly mounted, and will withstand shock and vibration better than any standard battery. AGM batteries have a very low self-discharge - from 1% to 3% per month is usual. This means that they can sit in storage for much longer periods without charging than standard batteries. Most AGM batteries can be almost fully recharged (95% or better) even after 30 days of being totally discharged. AGM batteries can cost 2-3 times more than a flooded cell equivalent.
Now, the chargers!!!
Battery Tender Plus by Deltran- This was my first smart charger, after I cooked a few batteries because I left the trickle charger on too long, this is what the dealer had in stock, at a price of about $70. I had this for about six years and never had an overcharged battery again. It has four charging modes, initialization, bulk charge, absorption charge and float mode. This charger worked great for about six years, and then I tripped over the cord. This caused the charger to fall off the shelf and crash on to the concrete garage floor. It never worked again. This charger is available in both 12v and 6v models (both are 1.25 amp charge rate), and is a very dependable smart charger. Has SAE style connector.
Optimate III by Tecmate- This was my purchase after I killed my Battery Tender, about $60. It can also desulfate neglected batteries, provided they have at least 2 volts. It is very simple to use and interpret, and is safe for any form of lead acid batteries. There are six LED’s on the face; power, reversed polarity, desulfates, charge, weak and good maintain test results. There are five steps to the charging process, detect battery condition, desulfate, bulk charge, absorption charge and maintenance mode. This charger charges at 0.6 amps and will charge almost any battery, although larger batteries require more time. It really does bring back dead batteries that other chargers won’t charge. This is one of my favorite chargers, simple to use and safe for long term connection. Has a KET style connector. Unfortunately I have more than one battery that I need to charge, so I also bought the…
Accumate V by Tecmate- this charger is a higher current charger than the Optimate 3. It has a 1.8- amp charge rate, and because it is a constant current charger, it charges faster than my 5-amp automatic tapering charger. So it is perfect for lawn and garden batteries, boat batteries, and pretty much any battery up to 100 AH. It is also safe for all lead acid batteries. I paid around $55 for the Accumate V. Has a KET style connector.
Accumate 6/12 Mini by Tecmate- So far, all of the other chargers I have talked about are 12 volt only. As by its name, the Mini is a 6 or 12-volt charger and can be purchased for $35. The Mini is much simpler in charging forms than the Battery Tender and the Optimate III. It has no recovery mode, so deeply discharged batteries won’t charge. It charges at 0.9 amps. If you need a recovery mode for 6-volt batteries, the Accumate 6/12 offers that for a little more money (and a 1.2 amp charge rate). This charger has a SAE style connector.
Optimate 4 by Tecmate- I got this charger for Christmas, although I think it retails for $70. It does the same thing as the Optimate III, but has a faster recovery mode, 48-hour time limit to prevent wasting time on hopeless batteries and a weatherproof casing. One thing is noticeable; it is a lot harder to determine what the charger is doing. Just because a LED is on, does not tell the whole story, other LED’s on and which ones are flashing can be used as a sort of schematic to interpret the currant state of things. The Optimate 4 is almost gimmicky for the sake of being gimmicky. And so far it has kept the battery in my FZ6 charged, at least that is what I think the charger is telling me. Overall the Optimate 4 is a nice charger, the new sleeker weatherproof case make the product much more attractive than the plastic gray box of the Optiamte III. I would not run out and purchase one to replace a working Optimate III or Battery Tender. The Optimate 4 has SAE style connectors.
If anyone has additional questions or wants more information, just let me know.
Justin
First order though is some info on basic battery types.
Flooded/Wet Cell- This is your standard type of battery. You have lead plates submersed in a sulfuric acid solution. You can have various types such as maintenance free, filler caps, starting, deep cycle, or marine duty, which is a cross between starting a deep cycle. The difference between deep cycle and starting is the design of the lead plates. In a starting battery you need maximum power for a short burst of time, so the lead plates have more of a 3D design. Think of a sponge versus a solid lead plate. This provides more surface area for more instant current draw. It also has a down side, all of those spaces in the plate can plug up with sulfur if the battery is drained too low. This sulfurization slows down the chemical reaction and reduces power. By contrast a deep cycle battery can withstand multiple deep discharges and still retain capacity. The more solid lead plates prevent sulfurization, or enable a charge to break up any accumulated sulfur. Deep cycle batteries trade reduced starting power for the ability to withstand deep discharges.
VRLA (Valve Regulated Lead Acid)- VRLA is a catchall for most forms of sealed batteries. Valves control the release of any gasses produced during the charge/discharge cycles. This provides, under normal circumstances, a recycling of the water that is released during the chemical reaction is recycled to the cells, so you never have to add water. If the battery is charged to fast, the valves will release any gasses to prevent a pressure build up. This will cause the electrolyte level to drop, since there is no way to add water, the battery will slowly die. This is why charging rates are very important to battery life. VRLA batteries can also be called MF (maintenance free) and spill proof. VRLA batteries can also have multiple types of electrolyte (including flooded cell), which will be explained next.
GEL Batteries- Can also be called gel cell. In this type of battery, the electrolyte is in the form of a gel like substance. This allows for a smaller more compact battery. All gel batteries are maintenance free and have some form of valve regulation. Gel batteries have a reputation of failing suddenly. This is due to the gel in contact with the plates becomes “dry”, reducing the chemical reaction. Since they are sealed, no additional water can be added. Again, charging and discharge rates need to be watched to prolong battery life.
AGM- Absorbed Glass Mat or Advanced Glass Mat. These batteries have the electrolyte held by glass mats between the lead plates. This is an advancement of the gel batteries. AGM batteries are more long-lived and less susceptible to overcharge/discharged damage. AGM batteries do not have any liquid to spill, and even under severe overcharge conditions hydrogen emission is far below any other form of battery. The plates in AGM batteries are tightly packed and rigidly mounted, and will withstand shock and vibration better than any standard battery. AGM batteries have a very low self-discharge - from 1% to 3% per month is usual. This means that they can sit in storage for much longer periods without charging than standard batteries. Most AGM batteries can be almost fully recharged (95% or better) even after 30 days of being totally discharged. AGM batteries can cost 2-3 times more than a flooded cell equivalent.
Now, the chargers!!!
Battery Tender Plus by Deltran- This was my first smart charger, after I cooked a few batteries because I left the trickle charger on too long, this is what the dealer had in stock, at a price of about $70. I had this for about six years and never had an overcharged battery again. It has four charging modes, initialization, bulk charge, absorption charge and float mode. This charger worked great for about six years, and then I tripped over the cord. This caused the charger to fall off the shelf and crash on to the concrete garage floor. It never worked again. This charger is available in both 12v and 6v models (both are 1.25 amp charge rate), and is a very dependable smart charger. Has SAE style connector.
Optimate III by Tecmate- This was my purchase after I killed my Battery Tender, about $60. It can also desulfate neglected batteries, provided they have at least 2 volts. It is very simple to use and interpret, and is safe for any form of lead acid batteries. There are six LED’s on the face; power, reversed polarity, desulfates, charge, weak and good maintain test results. There are five steps to the charging process, detect battery condition, desulfate, bulk charge, absorption charge and maintenance mode. This charger charges at 0.6 amps and will charge almost any battery, although larger batteries require more time. It really does bring back dead batteries that other chargers won’t charge. This is one of my favorite chargers, simple to use and safe for long term connection. Has a KET style connector. Unfortunately I have more than one battery that I need to charge, so I also bought the…
Accumate V by Tecmate- this charger is a higher current charger than the Optimate 3. It has a 1.8- amp charge rate, and because it is a constant current charger, it charges faster than my 5-amp automatic tapering charger. So it is perfect for lawn and garden batteries, boat batteries, and pretty much any battery up to 100 AH. It is also safe for all lead acid batteries. I paid around $55 for the Accumate V. Has a KET style connector.
Accumate 6/12 Mini by Tecmate- So far, all of the other chargers I have talked about are 12 volt only. As by its name, the Mini is a 6 or 12-volt charger and can be purchased for $35. The Mini is much simpler in charging forms than the Battery Tender and the Optimate III. It has no recovery mode, so deeply discharged batteries won’t charge. It charges at 0.9 amps. If you need a recovery mode for 6-volt batteries, the Accumate 6/12 offers that for a little more money (and a 1.2 amp charge rate). This charger has a SAE style connector.
Optimate 4 by Tecmate- I got this charger for Christmas, although I think it retails for $70. It does the same thing as the Optimate III, but has a faster recovery mode, 48-hour time limit to prevent wasting time on hopeless batteries and a weatherproof casing. One thing is noticeable; it is a lot harder to determine what the charger is doing. Just because a LED is on, does not tell the whole story, other LED’s on and which ones are flashing can be used as a sort of schematic to interpret the currant state of things. The Optimate 4 is almost gimmicky for the sake of being gimmicky. And so far it has kept the battery in my FZ6 charged, at least that is what I think the charger is telling me. Overall the Optimate 4 is a nice charger, the new sleeker weatherproof case make the product much more attractive than the plastic gray box of the Optiamte III. I would not run out and purchase one to replace a working Optimate III or Battery Tender. The Optimate 4 has SAE style connectors.
If anyone has additional questions or wants more information, just let me know.
Justin
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