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Do I need a dedicated battery charger?

oren_rokach

Well Known Member
I bought the "standard" acid concord battery 25RC for my Rv10 from Van's.
IF charging the battery is done via the alternator 14v voltage, why do I need a dedicated 200$+ charger, rather than connecting it to 14v power source?
 
flooded lead acid batteries are pretty tolerant of charging voltages and routine. Sealed lead acid are less tolerant and lithium even less tolerant.

For an FLA battery, any cheap charger (which is just a simple voltage regulated power supply) is fine.
 
AGM batteries like yours normally do not need to be charged if the aircraft is flown once per month or so.
The problem with a 14 volt power supply is that the voltage does not taper off over time.
A $200 charger is not needed. Use an inexpensive charger/maintainer and disconnect it after 24 hours or less.
Some aircraft owners have reported that battery maintainers do more harm than good if left connected continuously.
 
still the alternator is by far less stable than my bench voltage regular, no?

Alternators are used for a short period of time. Chargers used the same way will have no meaningful negative impact IF the float voltage recommended for the battery type is used. It is typically the multiple day float periods from simple charges (intelligent charger are often different depending upon how closely that intelligence matches what is good for the battery type) that kill the SLA and lithium batteries. Again, FLA batteries are pretty tolerant of long term simple float maintenance.
 
I think one very important fact or rather one very important question is being glossed over here...

WHY do you feel you need a charger? Is it to do regular maintenance charging in between flights?

If you answered yes to the question above then it's time you did some study on the Recombinant Gas (RG) battery technology which is the core of your RG25XC battery. (The RG in RG25 is an abbreviation of Recombinant Gas, the XC is for eXtra Cranking capacity.) These batteries have very low self-discharge rates. You can leave them for quite a long time without charging them and, unlike a flooded lead acid battery, they won't have self-discharged to the point of being flat.

Flooded lead acid batteries such as what we find in most of our cars have a fairly high self-discharge rate. It's this older technology that many of us grew up with, thus we are very familiar with the need to put a battery maintainer or trickle charger on the battery to keep it well charged during periods of disuse.

Flooded lead acid and Recombinant Gas are two totally different battery technologies. The RG battery does not need a battery maintainer or trickle charger. If you fly once a month that will be plenty to keep the battery in good shape. Perhaps not so much your engine, but at least your RG battery will be happy.

Don't apply the old "must keep it trickle charged" mindset from the days of flooded lead acid batteries to your new RG battery - treat the new battery as it is intended to be treated. No trickle charging is required.
 
The main reason, is that I got my battery, a year before I intend to do my first flight... but my avionics will go alive in a month, would want to do some testings
for battery longevity it is preferred to keep it fully charged
 
The main reason, is that I got my battery, a year before I intend to do my first flight... but my avionics will go alive in a month, would want to do some testings
for battery longevity it is preferred to keep it fully charged

Good reason to have a real power supply, not some dirty, noise ridden output battery charger. For ~$100 you can get a new, regulated 30 amp supply with adjustable output voltage. Do all your panel hangar flying with this and it will keep your battery topped off just like your alternator will.

As previously mentioned, never leave any charger connected to your battery for prolonged periods of time. Today’s RG batteries do better if you just let them sit (assuming they are first fully charged).

Here is a nice power supply: https://www.dxengineering.com/parts...MIyZv7--ST7AIVWtyGCh20kAecEAQYAiABEgLPPfD_BwE

Carl
 
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