The Black and Decker BCD-15 portable battery charger is an excellent option for keeping your batteries charged while RVing. While just about any good 12V automatic battery charger will do, this unit has a unique feature that is of particular use for the RVer. I have had one of these for several months now and here is my experience with it.
First off, why would you need a battery charger while RVing? No matter how you RV you are almost certainly dependent on batteries for power and mobility. Motorhomes, toads, tow vehicles and trailers all have batteries that are necessary for daily life and travel. Dead batteries in any of those can be a real headache when on the road. You should always carry something capable of getting your batteries charged up properly. Most motorhomes and trailers have built-in charging systems, but toads and tow vehicles generally do not. Unfortunately, the charging systems in many RVs, particularly travel trailers, are pretty much junk. They will not properly charge or maintain your batteries over the long haul. For these reasons, it is good to have a decent standalone charger that you can dedicate to the task. The Black and Decker BCD-15 is a great choice for this task. It is compact, light weight, durable, efficient and it can quickly charge most 12V batteries found in common RVs.
The Black and Decker BCD-15 is a standalone “benchtop” charger capable of delivering 15 amps of charging current with 4 primary features: Charge, Start Boost, Alternator Test and Battery Reconditioning.
The charge feature delivers up to 15 amps of current over a 3 stage charging process. It will bulk charge, boost charge and float charge. In the boost mode, the charger will get to about 14.7 volts and automatically hold there as the current drops to 1 amp or less. This is the indication it uses to determine full charge. It then drops to a 13.6V float charge until you turn it off or disconnect it. 15 Amps is sufficient to charge batteries up to about 200 amp hours in capacity in a reasonable amount of time. With that capacity it can easily handle most vehicle and trailer battery setups.
In boost start mode, the charger pushes 40 amps into the battery for 90 seconds. This will quickly get enough charge in a dead battery to start your vehicle. I have found it works pretty well.
The alternator check mode allows you to test your vehicle alternator with and without a load. While I have not done the test, the procedure in the manual appears simple to follow.
The most interesting feature is the battery reconditioning mode. We have two 6V deep cycle golf cart batteries on our travel trailer which total 225 AH. We spend most of our time attached to shore power so the batteries remain on trickle charge from our WFCO power center. While we are very diligent in maintaining proper water levels in these batteries they will inevitably loose 10 – 20% of their capacity per year due to sulfation on trickle charge. The main way to deal with sulfation on this type of battery is to do an equalization charge. Our power center does not have that option so we would have to do it with an outside power supply.
Equilization charging can be very dangerous and must be monitored carefully to avoid damaging your batteries or other surrounding equipment. The Black and Decker BCD-15 offers an interesting alternative called “battery reconditioning”. In this mode, the charger sends pulses of electricity through the batteries at a frequency which is said to dissolve the sulfate coating that builds up on the lead plates. Many people say this is a gimick that does not work. I thought for $55 it was worth a try.
Restoring Our Batteries:
To test it out, I disconnected the battery bank from the trailer and attached the leads from the BCD-15 to the proper terminals. I then ran a charge cycle to make sure the batteries were fully charged. Once the charge cycle was complete, I tested the cells with a hydrometer to get the cell specific gravities. They were all slightly different measuring between 1.225 and 1.250 – which is in the “Fair” range for these batteries and equates to having between 75% and 90% of their original capacity at full charge. Mind you, these batteries are only 10 months old. I then switched the charger into Battery Recondition mode and let it run. When in this mode, it appears as though nothing is happening. If you open the cells and look in there is no bubbling and no heat generation. These are the two big safety issues attached to doing equalization charges. This can also be used on sealed batteries as well, which equalization cannot. Given that, this appears to be a much safer way to bring life back to tired batteries.
The manual states that after 24 hours the cycle will stop and switch into charge mode. The charge will complete and then it will on float charge. Given that, you know it is done when it says “FLO” on the display and the needle shows 100% charge. If there are any problems during the process it will error out and indicate that on the screen. The manual also states that it can take up to 5 cycles to completely recondition a battery. After one cycle, I checked the specific gravity of each cell again and they were all exactly 1.250. This shows the cells had been equalized to 1.250. I ran another cycle and there was no change – still all at 1.250.
I repeated this 3 more times with no noticeable difference in the specific gravity. While the manual suggests giving up at this point I decided not to because I had noticed something during this process. The cycle time was closer to 32 hours rather then the 24 hours noted in the manual. I attributed this to the deep cycle 2 x 6V 225 AH battery bank I was running this on. The charger is really designed for standard automotive batteries which have less then 1/2 that capacity. I figured with twice the capacity there would be close to twice the lead surface area. This means it could take at least twice as long to work, so I pressed on. After about 2 weeks of continuous cycles I tested the cells again. This time it was 1.260 – which brings it up into the “good” range and within 0.005 units of a brand new battery, which I was quite pleased with.
The conclusion is that it does in fact work. It is much slower then equalizing, but we tend to sit for up to 3 months attached to shore power in a single location so that’s not a big issue. The safety factor greatly outweighs the time factor for me. Since purchasing this unit we have also had to use to get both our daily drivers back up and running and we plan to recondition the batteries in both of them soon as well.
I have Amazon links below for this unit and a hydrometer to test wet batteries. Home Depot also stocks these in most stores ans hydrometers are available at any major auto parts store.