Recommendations for a good quality trickle charger for off season storage

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I'm looking for a good quality trickle charger that I can hook up to my 1991 while in storage over the winter months.
Any recommendation?
 
ahhhh winter, but did have the S out Sunday!
 

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Is there a difference between a battery tender and a trickle charger.
I'm looking for something that can be connected for a long period of time (6 months )

Thanks for all your help
 
you want a tender-rony, and a roni is so right...I bet ya gonna love her for the rest of your battery life..

A trickle charger typically does not know when to quit and can overcharge..
 
I had problems with batteries not exceeding 2-3 years with the Ctek. But perhaps not its fault. I switched to Noco. Will see if it is better.

I have a CTEK that is older than RPM217's. Used it at the dealership on cars that had batteries getting low, to get them to full charge again. Hundreds of cars over many years. Now I rotate it between 5 or 6 cars over the winter in my garage. I sometimes wonder if I should still be using it, as it is so old! I handle it with care and examine the wiring and clamps often. It works the same now as it has for 20 plus years.
I also have a Battery Tender that maintains the NSX while it sleeps in the winters. It is probably 12 years old, and has performed perfectly.
I expect Asylum's batteries only lasting 2-3 years, possibly has more to do with the brand of batteries he's buying, as opposed to the charger, or there is an extra drain causing the issue. I put a new battery in the NSX when I got it, and replaced it after probably 6 years. The current one will soon be that old, and is still hanging in there, knock on wood!
 
In the winter months I use a Ctek MUS Polar on my Audi A4. The NSX is a plonker when it comes to parasitic loads compared to the Audi which has things like electric after run coolant pumps. If you live in a cold climate, be sure to check out the temperature operating limits . The NOCO, Battery Tender and some of the others that I checked out did not guarantee operation below -20C . The MUS Polar was the only maintainer that I could find with guaranteed cold weather operation (down to -30C).

I have never used a maintainer on my NSX when it goes into storage for the winter. I just make sure the battery is charged and disconnect the battery. That has worked just fine for 12 years with both the conventional flooded cell battery which was on the car when I got it and the AGM battery that is now on the car. AGM batteries in particular are excellent at being able to be put into storage and retain their charge. If you are putting the car into storage and don't plan to use it until it comes out of storage next spring, don't bother with a maintainer, just disconnect the battery negative terminal. If this is a case of very infrequent use on nice days then a maintainer would be a good idea.
 
In the winter months I use a Ctek MUS Polar on my Audi A4. The NSX is a plonker when it comes to parasitic loads compared to the Audi which has things like electric after run coolant pumps. If you live in a cold climate, be sure to check out the temperature operating limits . The NOCO, Battery Tender and some of the others that I checked out did not guarantee operation below -20C . The MUS Polar was the only maintainer that I could find with guaranteed cold weather operation (down to -30C).

I have never used a maintainer on my NSX when it goes into storage for the winter. I just make sure the battery is charged and disconnect the battery. That has worked just fine for 12 years with both the conventional flooded cell battery which was on the car when I got it and the AGM battery that is now on the car. AGM batteries in particular are excellent at being able to be put into storage and retain their charge. If you are putting the car into storage and don't plan to use it until it comes out of storage next spring, don't bother with a maintainer, just disconnect the battery negative terminal. If this is a case of very infrequent use on nice days then a maintainer would be a good idea.
I agree. The NSX has about a 500 mA drain just sitting there. Disconnecting the batt negative is probably the easiest way, but for those of us who drive their cars in the winter (Colorado is almost always sunny and dry, but cold), the maintainer is easier. Just unplug it and go. For those weeks like this one where we had a foot of snow and the car has to sit in the garage, the maintainer keeps it fresh.
 

So many choices with these. I wanted the basic to keep my battery charge while not in used

Thanks for all the help this is the one that I bought.

CTEK - 40-206 MXS 5.0 Fully Automatic 4.3 amp Battery Charger and Maintainer 12V

 
I agree. The NSX has about a 500 mA drain just sitting there. Disconnecting the batt negative is probably the easiest way, but for those of us who drive their cars in the winter (Colorado is almost always sunny and dry, but cold), the maintainer is easier. Just unplug it and go. For those weeks like this one where we had a foot of snow and the car has to sit in the garage, the maintainer keeps it fresh.
I think you slipped the decimal place :). The NSX seems to run at about 50 - 70 mA. I think most of the variability comes from the measuring device. Some multimeters use fairly high resistance measuring shunts on the low current measurement settings and that resistance can be high enough to reduce the voltage which drops the amount of current being measured from the true value.

My Audi A4 oinks out at an initial parasitic load current of almost 10 amps after engine shut down which eventually tapers off as all the fancy stuff eventually goes to sleep. Even then, it has one of those proximity smart keys and the systems are constantly pinging which complicates getting measurements. Checking for long term parasitic load is a hassle because its a wagon with the battery under the floor in the back storage area and all the doors have to be closed (or tricked closed) to get a good measurement. Leave your modern Audi in long term parking at the airport and I can pretty much guarantee you that you are coming back to a dead Audi.
 

So many choices with these. I wanted the basic to keep my battery charge while not in used

Thanks for all the help this is the one that I bought.

CTEK - 40-206 MXS 5.0 Fully Automatic 4.3 amp Battery Charger and Maintainer 12V


This is the battery tender that I have, it works great. Also, you can purchase a magnetic breakway connector for this, and mount it somewhere on the exterior of your car. Then no need to open/close the hood to attach the connector. Also, if you forget to disconnect and drive away, the cable just breaks away. I have this already installed on my Lotus and it's awesome, have another mag connector for the NSX that I'm going to install this winter. This is where I purchased mine (it's an aftermarket Lotus parts site): https://hethelsport.com/tools/charger-connection-kit/
 
I think you slipped the decimal place :). The NSX seems to run at about 50 - 70 mA.
Probably. :) I only know because I put a multimeter on the car when it was shut off during my re-wiring and alarm work on my 91. That was over 10 years ago lol. It may have been that the alarm itself was drawing the 500 mA...or I read the scale wrong!
 
Magnetic connection? I love my mag-safe connection on my MacBook Air.

I'm going with a battery tender with my Li+ battery. I'd like a magnetic connection, but I'm not interested in drilling a hole in my car for the HS unit, even on the bottom of the bumper. Anybody else have a magnetic connection they made work or some other way to protect my NSX from damage if I forget to disconnect? I can buy a random magnetic connector on amazon, but I'd love to go with something someone else has already made work. Who else stores their NSX 1/2 the year?

Anybody got a nice elegant solution?
 
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Ha first thing I do is check to see I pulled the connectors apart. Of course I did once leave it dragging on the ground and the little plastic cap tore off, now I just use painters tape..
 
Having retired from a large electric utility where we see lots of things catch fire, i sleep better having less things plugged in(or maybe it's those Tesla fire videos he-he). So i love just having a simple switch on the negative cable as suggested above, but i don't have a radio, so i don't lose any settings. My wifes 2006 RDX only lasts around 3 weeks parasitic. I've used the Odessy 925 for a long time. The inventor himself once told me that these batteries would suffer 250 dead drains! He lied, they are good for around a half dozen or so, but i get around 5-7 years out of them and they don't seem to lose anything over an entire winter. I understand that this may not be a good idea on newer vehicles that need to "relearn" so much every time the battery is disconnected, not to mention a ton of luxury setting stuff. I certainly don't want the fuel map messed with. Regarding the para loss, i also once got scary high reading, then i checked later and it has settled down to the under 50 range, so perhaps some "learning" may well be going on our old rides as well. In the states the "battery tender" brand was the gold standard for a couple of decades. It used to be a very tiny amperage with none or little electronic management, which i saw as good. I've never heard any issues with those tiny units. Although I'm hooked on the Schumacker brand 12/8/2 speed chargers that do have a trickle cycle for very small loads and do give you that cool % charge and voltage instant readings, the inexpensive "tender/maintainer" would be my preference. I'm a mechanical guy, not electrical, so just my thoughts.
 


I have a few of these on nsx and other car in garage for winter like the digital display , and got them thru Costco when they had them, no issues thus far few years in
 
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