What is the difference between a trickle charger and a battery tender? Suppose I wanted to purchase the last charger I will ever need. Is there something that can be both, and be used for jump starts and work for 6 volt and 12 volt batteries. Any recommendations would be great.
My son has a Power Wheels Harley that has 2, 6 volt 14Ah batteries. Currently I have a cheap 6 volt charger that takes around a day on each battery to charge it. I’m wondering if I can somehow charge them faster. I’ve been lead to believe that I can somehow wire them together and put a regular car charger on them and charge both in like an hour. Does that seem possible? How would I do it?
Does it actually take 2 batteries to run, or you have 2 batteries for it, which you use one at a time? If you install both at the same time, are they connected in series or parallel? And what kind of batteries are they? SLA, NiCd, NiMH or what?
You can only charge lead-acid batteries so fast without damaging them. About the only way to get a faster charge cycle would be to replace them with NiMH batteries.
Battery charger terms are ill-defined, but I’d say a trickle charger is always providing a charging current, however low, while a battery tender has a monitor that will reduce the charging to zero when it’s not needed.
A better way to look at chargers is between “smart” and “dumb” chargers.
A trickle charger is “dumb” in the sense that it is up to the user to disconnect the battery when it is fully charged. If it is not the electrolyte will eventually be boiled dry and the battery ruined. Smart chargers and/or battery tenders are designed to be connected indefinitely, they sense when the battery is charged and switch to a maintenance or “float charge” mode that will provide enough current to maintain a fully charged battery indefinitely. Their main purpose is for equipment that is used infrequently or stored between seasons.
Your application depends on how the batteries are used - are they connected in series or parallel? In either case they should be treated as a single battery, electrically speaking.
Battery chargers should be “sized” to the battery they are charging. A “tender” is not a good choice for a pair of huge automotive start batteries that are completely dead or discharged. On the other hand excessive charge currents are fast, but can damage the internal plates. Battery charging currents are a compromise between safe currents and reasonable charging time. Usually about 10 to 20 percent of the ampere hour rating.
This is the best website I’ve come across for lead-acid automotive type batteries:
Thanks everyone for the replies especially CT. It sounds like I could get a 6v, 2 amp charger and cut my charge time in half but wouldn’t want a 15 amp charger. I’m thinking I’ll buy a charger for both 6v and 12v that has 100/15/2 amp options. Pretty good multitasker for the garage.