NEXPEAK 10-Amp Car Battery Charger, 12V and 24V Smart Fully Automatic Battery Trickle Charger Maintainer w/Temp Compensation for Truck Motorcycle Lawn Mower Boat Marine Lead Acid Batteries

I bought this battery maintainer/charger for my cars. My Mercedes has an AGM battery; this maintainer has AGM battery charging portions with standard and other battery options built in. I changed my Mercedes battery to 100% today, and now I am charging my Sienna battery. The only complaint I have is that the cord to the wall outlet is too small. It should be 5ft or so. It is very easy to connect. The RED clamp connects to the RED port of the battery, and the Black clamp goes to the earthing port. I give you a percentage for he change where you start, for example, 40%, then flash to 100%, unit battery is 100% change. After full changed, a FULL sign appears and the fan stops and charging stops automatically.Thanks!Manny

Great product. I use it on my motorhome to maintain the batteries while stored.

As described. Shipped and rec’d on time. Good value (< $21). Works well. Easy to use.

I purchased this Nexpeak 10-Amp 12V / 5-Amp 24V Smart Car Battery Charger for just $23.25 from the manufacturer in April-2023, but Amazon handled fulfillment. Shipping was free via Amazon Prime.This is a great value. My old Craftsman charger from the early 1980s finally died (and I needed a "smart" charger for my Jeep's AGM battery). That old model cost way more and had way less features than this new Nexpeak model.The box and User Guide identified my new charger as model NC201. Mine is all black and you'll see an identical one that is orange and black for sale on Amazon, too. Strangely, the orange/black model is usually priced higher. The black/black model I purchased stated that its price was available only to Amazon Prime members.There are many great features that you can read about on Amazon's product page for this charger. So I'll limit my review to some of the gotchas that may cause trouble. I'm listing them as "Cautions" because they could be deal-breakers for some buyers. Just remember the price -- if you want a better smart charger, you must be prepared to spend much more.Cautions to be aware of with this NC201 smart charger:=============================================================================1 - English is not the native language of Nexpeak and their User Guide has a few typos at key locations that make their instructions and descriptions unintelligible.2 - There is no on/off switch for this charger and this can place the user at grave risk of harm or death. Seriously! Connecting the charger is a two step process. First, connect the charger to your battery. Second, connect the charger to a suitable AC outlet. (Disconnecting is the reverse.) Here's the problem: When you first connect the second battery clamp to the battery terminal, a significant spark will jump between the battery terminal and the clamp. Again, when you connect the charger's AC plug to an AC receptacle (or extension cable), another powerful spark will jump between the plug and receptacle. If there is ANY FLAMMABLE GAS nearby---if your battery is not sealed and is expelling hydrogen gas---it could ruin your day and maybe even your life. So you MUST use this charger in a well ventilated area. The only exception would be if you are using ONLY sealed batteries that are actually sealed.3 - The battery MUST be disconnected from the vehicle if the "Repair" (a.k.a. "Pulse" mode) feature is used or the charger may damage some of the electronics devices in your vehicle. (This is mentioned in the User Guide, but it can be easily overlooked.) Why disconnect? Answer: Because the Repair feature will pulse a higher-than-normal voltage into the battery and, if the battery is still connected to the vehicle, this higher voltage can damage some of the electronics (engine control module, vehicle microprocessors, radio, GPS, clock, etc). And that's not all: If your battery is damaged (for example one or more cells are shorted), the Repair feature may cause your battery to overheat. One user posted a photo of their battery with a huge hole in the top after it exploded while a charger was attached. This means you should not leave the battery unattended during a Repair operation. You'll need to periodically check to make sure it is not getting hot. If you determine that it is getting hot, you should immediately disconnect the charger and replace the battery.4 - The Nexpeak charger I received did not read the voltage accurately. It consistently indicated a voltage value that was 0.2 volts low. For example, when my battery was 12.63 V (measured with an accurate voltmeter), the charger displayed 12.4 V. Again, when my battery was 13.06 V (after being charged -- its an AGM battery), the charger read 12.8 V. This is bad because it can cause you to assume a battery is bad when it may still be good. Worse, it may cause the charger to over-charge in some circumstances.5 - There is a "Mode Selection" switch located to the right of the LCD display. This switch is used to select one of the five provided modes (STD, AGM/GEL, WET, MOTORCYCLE, REPAIR). The Mode Selection switch is only active during the first 25 seconds after the charger is connected to the battery but NOT yet connected to AC. As soon as the charger is connected to AC (which causes charging to begin) or after 25 seconds (if it's connected only to the battery), the Mode Selection switch will be locked and you will not be able to select a different mode. So, you MUST select the desired mode after you connect the charger to the battery but BEFORE you connect to the AC. And you'll have only 25 seconds. If the time expires or charging has begun, the only way to change the mode is to disconnect the charger from BOTH the AC and the battery and start over.6 - The LCD display has a very, very, very narrow viewing angle. You must face it straight on to read it. I would never tolerate this on an expensive model. But for $23.25 its entirely accepted (even if it is undesired).7 - This model has a wonderful temperature compensation feature. If the temperature is 10°C (50°F) or lower, it will use a "winter" mode which prevents the battery from being under-charged. If the temperature is over 28°C (82.4°F), it will use a "summer" mode which prevents the battery from being over-charged. Here's the problem: There appears to be no way to configure the charger to display the temperature in Fahrenheit. It only displays a Centigrade (Celsius) value.8 - When you use the Repair mode the charger will display "PUL" (for "pulse"). After the repair is finished, the charger will automatically begin charging the battery. Once the battery is charged, it will display "FUL" to let you know the battery is now at "full" capacity. But this is not actually true. When "FUL" is displayed what really happens is the charger stops charging at full amperage and switches to trickle charging with a low amperage. It will continue to trickle charge for 2 hours. At the end of the 2 hours it will stop all charging and display "OFF". When "OFF" is displayed is the only time that I was able to disconnect the charger from the AC and the battery without sparks (as described in #2 above). See more about "FUL" in #9 below.9 - The User Guide recommends that you allow the battery to charge for 2 more hours AFTER it displays "FUL". It explains that this is the way to top off the battery to its full voltage. This is true. When I charged a new AGM battery and the charger displayed "FUL" it had only reached 12.63 V (and the charger reported 12.4 V -- see #4 above). However, the "FUL" indication also identifies when the charger has switched to trickle charging and I left the charger connected to my battery for the 2 extra hours to see what it would do. At the end of the 2 hours, it displayed "OFF" and all charging ended. I measured the battery voltage again it was now up to 13.06 V (and the charger reported 12.8 V -- see #4 above). Note: The normal resting voltage for my Jeep's DieHard 34-AGM battery is 13.0 to 13.1 V. If you need to use trickle charging for longer than 2 hours (or exclusively), the User Guide says to use the MOTORCYCLE mode.=============================================================================I hope the above "Cautions" do not give you the impression that I disliked this charger. As I stated above, I believe it is a great value. I was surprised to find so many excellent features at such a low price. This is why I give it 4 stars.Some have criticized this model for its short cables and I disagree. First, because the unit includes an onboard temperature sensor to adjust the charge mode, it must be located very close to the battery so the temperature of the charger matches the environment of the battery. Second, I have never used a charger without an extension cord. Even the ones that had a longer cord, it was never long enough. Some have also criticized the wire gauge of the cables and this is rubbish also. The required wire gauge is solely a function of resistance. If the cable is short, there will be less resistance and a smaller gauge can be used. This is why the charger can safely get away with such "light" cables for connection to both the battery and the AC source.Bottom Line: I recommend this charger if you understand electricity -- you should have no problem using this charger, even with the above cautions. However, if you are a novice with little tech automotive experience (and no electrical experience---for example, you have no idea what "Ohms Law" is) then you should probably buy a more expensive model that's a little more forgiving.

Love the product and very useful

Used this charger several times to maintain battery charge & health. Using it on my AGM battery was slightly different but showed improved health with a follow-up battery tester. For the AGM batt, I had to press mode once to select the AGM option (with leads connected - but power cord unplugged).I don't think the DFS / Desulfate step applies to AGM batteries.I was able to charge from the positive lead under hood, rather than going to the battery (in trunk).Here are the steps I follow:1. Connect leads to + & - battery power. Observe readouts.2. Change mode unless charging standard battery.3. Connect to power - plug it in. Observe readouts.4. Full appears when the charging stops - but wait for the next status "Off".5. OFF readout appears an hour or so after FULL. Unsure but seems complete after it says OFF.6. Unplug power plug - observe readouts for voltage level.7. Disconnect + & - leads - all done!

Love the digital read outs, easy to use. Instructions are nicely made and easy to understand. Would recommend this product if you are trying to charge 12v ACM batteries and Car batteries.