Top 10 best Battery Chargers 2022 For Cost Saving

Temperature-compensated state-of-charge tables are available at batteryfaq.org. An IR thermometer makes it easy to check the temperature of a battery case (below the water line). I switched to the voltage method about 40 years ago, partly because I didn’t like messing with acid. (You can keep acid fumes off the terminals by using a cotton swab to apply an invisibly small amount of silicone grease to the seam where the plastic case meets the metal battery post.)(I have come back to using a pointer hydrometer sometimes. It will show if there’s a bad cell. It can also detect stratification. Charging can cause water to rise. A battery won’t charge fully until the electrolyte mixes evenly. Sometimes in cold conditions, it won’t mix, and not getting a full charge occasionally, will shorten a battery’s life.)Before checking a battery that has recently been on an alternator or charger, they say you should dissipate the surface charge by running the headlights ten seconds or letting the battery sit a few hours. In fact, it can take days. The colder a battery is, the longer it takes. An old battery may need days even at room temperature. I think “surface charge” is acid that hasn’t had time to permeate the electrolyte evenly after charging. Cold electrolyte is sluggish, and an old battery may have restricted pores.The most common causes of battery failure are chronic undercharging (sulfate remains on plates long enough to harden), and chronic overcharging, ( plate material corrodes and flakes off). They’re bound to happen with DC charging. Manufacturers of alternators and chargers want a voltage that’s a happy medium.I’d occasionally put an undercharged battery on a regulated charger overnight. Overall, it helped, but sometimes it made a battery worse. I can guess why. DC charging tends to produce bubbles. If a gas bubble blocks a pore in a plate, continued charging can seal the pore permanently. Also, in a low-maintenance battery, DC charging can cause calcium in a positive grid gradually to migrate to the lead oxide, grab oxygen, and form an insulating layer of calcium oxide.Early in 2002, a neighbor discarded a 2-year-old battery that was out of warranty and would no longer start his car. Several months later, I used it to test an antique Sears charger I’d found. The charger restored it so well that I put it on my car. Every three months, I’d charge it overnight. That derelict battery gave me 11 years of reliable service.An oscilloscope showed me that instead of DC, the charger produced 2-millisecond pulses. Charles Cady had invented it in 1959. He didn’t say it would restore a battery. He said it could continually charge a battery without damaging it. Nowadays, most smart chargers seem to use pulses. Battery chemistry can recover between pulses. Hydrogen and oxygen ions can better form water instead of bubbles. Metals like calcium tend less to migrate.A scope showed that the Schumacher SC-1200A/CA was charging my car battery in bursts of 50 milliseconds approximately 500 milliseconds apart. The microprocessor probably changes the timing according to conditions. I know it changes the voltage. Sometimes it will charge at ~13.2 all the way to shutoff. Other times, it will switch to ~15.5 to top the battery off. It may start ~15.5.When I topped off a battery that was at 98%, I watched the Schumacher apply 15.5 volts for half an hour. I had the filler caps off to watch the plates and electrolyte with a flashlight. With a DC charger, I would have expected to see bubbles sticking to the plates. I didn’t see any.The Schumacher is easy to fetch because it’s light. It’s easy to position because it’s fairly small and has no exposed metal except the clamps. When turned on, the charger takes 20 seconds to show a percentage estimate. Then it applies a trickle charge for a minute before beginning to ramp up to a rate that seems to depend on what the microprocessor has detected about the battery.I’ve read complaints that it may shut off too soon. Schumacher’s FAQ says it can happen with a cold battery. I tried it when my battery was at 25 F. It was at 77% charge, so it should have required at least 10 amp hours. In less than 1 amp hour, the charger said it was charged and shut off. The sluggish mixing of frigid electrolyte must have fooled the processor. (I think the sluggish electrolyte also affected my voltage check. Opening the door to release the hood latch would have pulled down the voltage a little, and it would have recovered slowly. It was probably about 82% charged.) In the cold, I could have used a manual charger, but there was no urgency, and maybe charging with sluggish electrolyte is a bad idea, anyway.Even at mild temperatures, when I check voltage the next day, I may find that the charger shut off a little too soon. Maybe the acid needed more time to mix. No problem. When I get a chance, I let the charger top it off.It’s the best lead-acid charger I’ve used, but I’ve found annoyances.1. The 20-page manual is made of 5 sheets of 8.5 x 11” paper. It tells the user to read it before each use, but that’s asking a lot. It’s poorly organized and in two languages. With an extra sheet of paper, they could staple two 12-page manuals, English and Spanish, each with a table of contents and the important reminders visible at a glance.2. The manual hasn’t been proofread. For example, Section 2 on page 2 says it’s only for 6-volt batteries of 24 AH and 12-volt batteries of 44-75 AH, and it’s only for starter batteries. That’s ridiculous. Page 6 contradicts these limitations, using batteries of 8 to 105 AH and 300 to 1000 CCA as examples.3. Page 9 says if it fails within 2 years, Customer Service will give you an RMA. After several months, I noticed page 19, at the end of the Spanish section. It has two warranty-program-registration coupons, one in Spanish, and one in English. It says you should cut it out and mail it in within 30 days of purchase. It doesn’t actually say I’ve waived my warranty, but it implies it. I don’t like that.4. The labels for the nine lights and two buttons are small like newspaper text. If the light isn’t good, I need to fetch reading glasses and maybe a flashlight. The display stays on only a minute. After that, if I want to check, I have to push a button. Accidentally pushing twice will shut the charger off.5.The percent reading can say 75% when a battery is 97% charged or 34% when it’s completely discharged. The reading can rise impossibly fast or stay the same while a couple of amp hours go into the battery. The percent display is bound to be problematic. Schumacher’s FAQ says it shuts off by recognizing a charging curve, and it’s most accurate if left alone. There wouldn’t be much of a curve at the start.6. There is no ammeter. I keep my Kill-a-watt P4400 (under $20) on the end of the power cord. The charger produces about 1 amp for every 20 watts input, so the watt meter serves as an ammeter. It also keeps track of how long the charger has been plugged in and how many amp hours have gone to the battery. The KWH display reads to 0.01. I ignore the decimal and divide by two: 0.08 KWH means 4 amp hours went into the battery.7. The manual says it’s charged when the green light pulsates (growing dim every 8 seconds). The charger may display 100% and a green light long before that. After I became aware of the green light, I’ve seen it continue to charge at 4.5 amps for 25 minutes or 3 amps for 50 minutes, before it switched off and the light pulsated.Another time, I watched the green light for two hours as the current tapered from 4 amps to 1 amp and finally shut off, and the light started to pulse. Since then, the battery’s impedance has been lower than before, so I think maybe desulfation took place. If a steady green light indicates “desulfation mode,” perhaps Schumacher doesn’t say it because some experts say there’s no such thing.A processor may use “zero delta,” a point when charging voltage stops rising, to determine when charging is complete. Instead of desulfation, a steady green light might mean ambiguity, that charging is complete according to the computed curve, but zero delta has not been detected. A third possibility is that a steady green means both. The SC-1200A-CA designers may have found that if the processor doesn’t see zero delta, that means optional extra charging is in order, to clear up old sulfate.*********A car had sat in a neighbor’s yard two months. She said the battery had been run down trying to start it after running out of gas. I thought maybe air had to be purged through the injectors. The battery would only click the solenoid, although my meter and my charger both said it was 50% charged. At one time, I would have thought a battery that sulfated should be junked.After charging, the battery gave me a lot of rapid cranking (resting about half the time). When it slowed slightly, I recharged it. The second time, it performed significantly longer than the first.************I’ve read that the SC-1200A-CA wouldn’t charge a battery if the voltage had fallen too low. A neighbor’s car battery was down to 0.8 V. I thought I’d have to start out with a dumb charger, but the SC-1200A/CA had no trouble. If sometimes this model hasn’t worked on a low battery, maybe the temperature of the battery was a factor.**********A neighbor has an antique that may require extensive cranking because it may sit for months and the choke doesn’t work. He’d sometimes leave his manual charger on the battery for days. One day when it sounded very week, I let my Schumacher put 48 AH into it. The next day, I found that the voltage had hardly risen, and now it wouldn’t turn the engine.Strangely, after it sat on the ground several weeks, the Schumacher charged it quickly. The engine needed a lot of cranking the next day. The battery provided an outstanding 11 cranking volts, and it didn’t slow at all. Another rejuvenation!Apparently, four years of overcharging with DC had caused calcium oxide to build up until the plates could not be charged. My first attempt to charge must have broken down the calcium oxide, but the freed calcium needed time to migrate back into the grid alloy.**********My two-year battery was three years old when I bought the SC-1200-A/CA. The battery charged at 3 amps, which was slower than similar batteries, and it supplied less voltage to headlights. After a year, I tried something new. Before topping it off with the charger, I used the parking lights to draw it down about 20%. Since then, it has charged at 4.5 amps and supplied more voltage to headlights. I guess 1-second bursts of cranking aren’t enough exercise to keep a starter battery in shape.**********A neighbor was about to replace a pair of 35 AH AGM wheelchair batteries because they were good for only 20 minutes of intermittent use. The wheelchair used an automatic DC charger. I put a 6 amp load on each of them for two hours, then charged with my SC-1200A/CA. His chair was faster than before, and he he said it would go all day on a charge.***********I’d owned the charger 10 months when it quit working. The display said it was charging, but the watt meter showed that it had shut off after a minute. I tried three times with two batteries. It had worked the day before, but two days before, there had been a drizzling shower while I was charging in the carport. The case hadn’t gotten wet, but maybe the cooling fan had drawn in moisture. I put the charger in a warm, dry place (115 F) for three hours. When I plugged it in, it worked again.***********I’d had the charger two years when I went to top off my car battery. According to the state of charge, it needed more than 10 amp hours, but after 2 amp hours, the charger switched to a pulsing green light and said it was fully charged. A test instrument found that I had more than a milliohm of resistance at the connections between the battery posts and terminals. I clipped the charger directly to the battery posts, and it gave the battery another 11 amp hours. I guess a tiny bit of resistance can fool the charger’s processor, and it works most reliably when clipped directly to the battery posts.***********When my two-year battery was five years old, it began self-discharging at 5% per day, dropping by 1/3 in a week and 1/2 in ten days. The alternator was working normally and the parasitic drain was only 10ma.I’d always thought that a car battery that wouldn’t hold a charge had to be replaced. With nothing to lose, I turned on the lights to draw it down about 20%, then charged with the SC-1200-A/CA. That was six months ago. It has been fine ever since. Dendrites can grow like cobwebs in a battery, forming paths for self-discharge. It looks as if the smart charger cleaned up the dendrites.*************I’d owned it 3-1/2 years when I again encountered the problem where the amber light said it was charging but the watt meter said it wasn’t. Twenty minutes in a warm oven got it working. I got it apart by removing four screws. Two were under the lower corners of the display panel sticker. Inside I found a bit of leaf, showing that the fan can draw in debris. In one of the intakes was silk thread as if a bug had begun spinning a cocoon. The processor was soldered to a board on the display panel. The leads had no protection to keep dirt and dampness between leads from causing trouble.I cleaned it with contact cleaner and a brush. One of these days, I’ll take it apart again and spray on a conformal coating. This is a sensitive circuit that’s bound to get dirt and humidity from the cooling air. I’m disappointed that Schumacher didn’t apply a protective coating.

The instructions are VERY hard to follow – because they made a lot of assumptions.This is to try and help those who were wondering. You’ve got 3 things to verify first.1: What KIND of battery are you charging? This is critical and you can only know this by searching the label on Google to figure out if it’s AGM, Lithium or other. (For purposes of this writeup I am assuming you got rid of your old clunker years ago and thus your car came with an AGM battery. Most cars sold after 2012-ish are going to have AGM and if it’s a hybrid it’s almost certainly an AGM. If it’s not AGM you’ll want to research your specific type.)2: What problem are you trying to solve? Sounds simple but it isn’t. There’s a difference between a DAMAGED battery, a DRAINED battery (as in there’s no charge at all) and a LOW battery. A DAMAGED battery is unlikely if this is the first time you’ve had an issue. A DRAINED battery is likely if your car (or whatever device) hasn’t been driven or even turned on in at least two weeks. A LOW battery may indicate the battery needs to be replaced. This device can help with all three, but it’s critical you understand what YOUR situation is. If you don’t know, don’t just buy this, get it towed to Autozone or whatever; they test batteries for free.3: How urgent is your problem? Meaning, if you’re stranded somewhere, you need to be calling a tow truck instead of researching this; it’s not going to help UNLESS you’re very near a power outlet. If you’re at home you’re probably fine, but you’ll likely need an extension cable depending on how your place is laid out.OK, so after that, here’s the run down.1️⃣ connect the charging cables to the device, then attach the charging cables TO THE BATTERY – DON’T PLUG IT INTO THE WALL YET. If you have a hybrid I know they say jump it from under the hood – don’t. Just attach straight to the battery (for hybrids it’s likely in the trunk behind a side panel). The reason for this is that there could be a defect in the line (thus why your battery’s in the state that it’s in). There should be one “pole” or post that has a (+) sign, that’s positive, or look for it under a red colored rubber cover. Connect positive (red) to this, then connect negative (black) to the other post, BEFORE plugging the device into the wall. Attach to the battery first. If your battery isn’t dead, you may get a spark, that’s fine. It’s a clue that your battery still has at least some juice.2️⃣ plug the device into the wall outlet. The device should get an amber standby light (the power symbol). If you don’t get this check if your outlet is one that has a fuse breaker (the two buttons) and see if you can reset it. Also verify this outlet has power; plug something else in; might also be powered by a switch somewhere. In other words CHECK THE OUTLET BEFORE YOU ASSUME THE DEVICE IS DEFECTIVE. If you check all that and still don’t get a base amber light, the device MIGHT be defective; but check step 3 first.3️⃣ Tap the MODE button once; it does take a bit of effort to push it in. It should light up 12v. (if nothing happens, it’s likely defective). DON’T LEAVE IT ON 12v. Keep tapping until those lights are off (and ideally the amber status light goes back on). This is where you need to know the battery type; it’s likely one of these three. HOWEVER…THIS SETTING IS FOR MAINTENANCE AND TRICKLE CHARGE, NOT FROM-ZERO CHARGING. So chances are, if you bought this device, this setting is NOT what you need YET. Proceed to Step 4 (this step was just to test the device to make sure it wasn’t DOA).4️⃣ This is a bit tricky – but tap the MODE button once (lights up 12v), then TAP AND HOLD for 3 seconds (literally count alligators in your head), then release (yes, you need to say “alligator” the third time). The light should go down to the second row with 6v on the right. Now, you’re back to tapping and the light will cycle to the left.IF YOUR BATTERY IS NOT DAMAGED – and the way you’d know that is whether it holds a charge or not – YOU WANT “12v Supply”. This will not give you an obvious indicator level, but if you need to jump this car, this will let you do it. It’ll basically give enough juice to the battery to allow it to turn over – use the car’s interior lighting as a clue. You may need to leave it on for a half hour or so just to make sure there’s enough for the initial draw. (Once you can get the gas engine going the alternator will complete the charge after you drive for about 30 minutes; otherwise see Step 5).So basically treat “12v Supply” like a jump. It’ll give you enough to complete the charge; if it doesn’t hold, you can then go to “12v Repair” and let it cycle, but that’s only if the battery has been dry for a very long time, usually. DO NOT LEAVE THE BATTERY PLUGGED IN ON 12V SUPPLY THINKING YOU’RE DOING GOOD – YOU’RE GOING TO DAMAGE THE BATTERY AND LIKELY CAUSE MORE PROBLEMS. This is because at some point there’s going to be feedback going the other way. That’s NOT what you want.5️⃣ After it’s been on “12v Supply” for about 30 minutes to an hour – just enough to have some base life, you can now tap MODE twice to go back to the maintenance mode I mentioned before, then (and this is critical) TAP UNTIL THE TYPE OF BATTERY YOU HAVE IS LIT. This is so that the charger will provide charge in a way that is healthy to the battery.You will also get the level indicator at the top to start working correctly (this works even if the battery’s dry, but from dry, it can’t hold enough charge to increase; you’ll just see it bounce from one to two and back to one over and over again while lights flicker. That’s why you have to do “12v Supply” first to give it enough to hold from regular draw (your car is always drawing from the battery for something or other), THEN do the maintenance setting if you want to go all the way to full and keep it there if you can’t (or don’t want to) drive it right away.One possible misconception with this device is the assumption it does all of the above automagically. It does NOT. You can leave it on maintenance mode but it’ll never charge, I promise you, and you can leave it on 12v Supply but you’ll have a problem if it charges for too long. 12v Repair seems to be more about testing the drain, so I suspect it won’t “harm” anything, but it likely will shorten the life of the battery if left on too long, especially if you don’t actually need it. Put it this way – if you’ve never had a problem starting your car until that ONE time during the pandemic that you stopped driving for weeks, you likely DON’T need 12v Repair. You likely just need to charge it up a bit, then put it in maintenance mode for however many days until you next drive; I would even suggest not leaving it plugged in but maybe plug it up for maintenance mode once a week or something for a few hours, just so that there’s drain-and-charge.6️⃣ Once you get the green indicator the device believes that the battery is full. At this point you can (theoretically) leave it connected in maintenance mode, or just plug it in as needed. To remove the device, remove things in REVERSE ORDER – Tap MODE until it’s in standby again, then remove negative (SET IT A VERY GOOD DISTANCE AWAY FROM METAL), then positive (SET IT A VERY GOOD DISTANCE AWAY FROM NEGATIVE AND METAL), uncouple the charging cables, then unplug the device from the wall.You are (or should be) done.One other thing I might suggest to you is to consider a portable AC generator. They go for fairly cheap here on Amazon – that way if you do get stranded somewhere that doesn’t have a power outlet, you can use those for that initial jump. Something else to consider for your emergency roadside (self) assistance. I have two emergency type devices – one’s a powerbank: https://www.amazon.com/gp/product/B07LBLQ9YY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1The other is an actual portable generator: https://www.amazon.com/gp/product/B07MYT6SZ5/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 (no longer available, but you can look some of the related similar products) which has other helpers like a light and USB outlets – could be a saver if you’re literally in the middle of nowhere when your battery acts up.

The unit will create sizeable spark when connecting the leads to the battery. This is with the 110 cable still unplugged. You will be greeted with large alarm sound as well. Apparently the designers thought the current to activate the alarm was worth the sparks. The Product description states “spark free system”- yet nowhere in the manual or box is this stated. So there’s that.I was initially having issues changing modes using the fingerprint icon button. I finally discovered there was a clear anti static/protective cover over the display. Once I removed that, it operates fine. Just in case anyone else missed this – ahem.I just noticed there is a newer version of this item available for another 5 dollars. Would have been nice to know that sooner. It appears to be mostly similar with faster charging claims- yet no statement on increased amperage. So they changed the charging algorithm? Don’t care. This unit if fine. Mostly. lets move on shall we?I first put it on a newly installed tractor battery that had been charged by my mower for 2 hours. The little red charging wonder immediately went to work. After 2 minutes, it turned itself off and and stated as much with “OFF” in the digital window. Cool.Next I noticed something annoying to only Americans- All temperature units are in Celsius. Forever. If that bother you, here is the formula. Memorize it. There will be a test later. (0°C × 9/5) + 32 = 32°FNext up, I placed on a car that gets driven once a week. Today’s vehicles have huge parasitic draws. I know this because I am a retired automotive Electrical Engineer. Target sit time is 30 days with a new battery. That’s the requirement. However, once all the defective software is loaded into the 28 modules splattered about the car, reality sets in, and the usual sit time is around 14 days. The little charger went to work again, happily informing me in Celsius of its monitored temperature, battery voltage and how many amps it was letting into my abused battery that constantly being attacked by 28 evil modules. Remember- the battery has many enemies. We lived by that statement in Engineering. So after 15 hours, it brought the battery up to 14.3 volts- and its still just idling there happily. I assume some day it will top out, but I’m calling it good for now. As for construction. Ahem. The “clamps” for placing on the battery are- quite possibly the cheapest looking things I have seen this side of a Barbie play house. Not the old Barbie stuff. The new ones. And That may be a disservice to Barbie. Sorry. I suspect the clamps will last long enough to get it past the return window- but I have my doubts. So does Barbie.The power cord is embarrassingly short. This one will never make it into the movies. For sure. If you plan on keeping this, You will need a 10 ft cord or so to just keep with this thing. I hat using a 100 ft cord when all I need is a few feet. To be fair, the cord length is given in the product description and is correct.I have not tested the other capabilities of repair and AGM battery use- but neither of the ose features interest me at the moment. I am bored with it and typing this so here it is-..The unit is worth 25 bucks. Buy it. It replaced a 30 yr old shumaker 2 amp unit I had. This new one with shut itself off, vary charging rate starting at 8 amps, and compensate all for ambient temperature to prevent issues. I can replace the clamps when they go bad. I kept the old ones.

This charger did not make it past 4 uses. I used it today to charge a 45ah battery pack. After an hour, I noticed that the charger had smoke coming from it. I looked at the display to find it not working and the charger was extremely hot. I unplugged it and set it outside where it continued to smolder. After the charger cooled down, I took it apart and found one of the capacitors had exploded. Part of the capacitor was stuck to the back of the charger when I took it off.I do not recommend this charger. Find another brand that isn’t sold by Amazon. Chinese junk…UPDATE 10/03/2022The vendor reached out to me directly and addressed the issue I had with their product. They sent me a brand new charger as the other was still under warranty. I’ve adjusted my rating based on their customer service and their promptness to rectify the situation. Further updates to come as the new charger gets used.UPDATE 11/12/22I finally put the new charger to use. After 20 minutes of charging my battery pack the unit did not get as hot to the touch as the first one would have. I’m pleased with the outcome, and I’m grateful that the customer service department reached out to me.

I’m a greenhorn at car-care, but this product was pretty much foolproof! I’m using it to keep the battery topped off for my family member’s car, as she has just had surgery and won’t be driving for 2 months. I do not need it for months and months of storage and maintenance, so the 2018-era reviews complaining about “now it only lasts for one year” after the manufacturer’s move to China, really don’t matter to me!I really appreciate the built-in safety feature of no sparking if you touch the clips together. Current won’t flow through this product, even when connected to the outlet, until it senses 3 volts. This could make it hard to charge a TOTALLY dead battery with this product, but it worked perfectly for us.To put this thing together, you’ll have to pick either small-ring connectors – which are for the non-car uses that will sit for over 6 months, like an ATV or motorcycle or boat – or the alligator clips, which are for cars and bigger engines that will be connected for just a few months. You’ll also have to have color vision to discern between red and black, since the alligator clips confusingly have a (+) symbol on one side of their jaws. On the second jaw, they differ (+) and (-), so if you can’t tell them apart at first glanceThe most difficult part for me was step 6e/f in the instruction manual – determine if your car engine has negative-ground or positive-ground status. Like I said, I’m a greenhorn here. Sure, the manual says “most cars” are negative-grounded, but I didn’t want to mess it up, cuz car batteries are big hefty things you don’t play around with. After real careful inspection, I found that the battery of our car had a wire going directly onto and behind the hefty metal of the vehicle body or “chassis” I learned it is called, which came from the (-) side of the battery. The (+) side had a complicated plastic cover over it, which made connecting the alligator clip a bit difficult, and that side’s wire led to other engine parts. That’s what made me 90% sure that the negative side was the “grounded” side. So I connected the (-) black clip to the (-) side of the battery, and the red clip to a nut-and-bolt part of the engine. I was able to close the hood on the car most of the way by turning the clips sideways and flat as I could. It’s not latched at the moment, but sitting in our garage, it should be plenty protected from spiderwebs and dust and whatnot. No option in our case to thread the cable thru the front grille since it’s pretty jam-packed with engine parts right behind it.My one complaint about this product is that the cable ending in the two alligator clips splits pretty close to the jaws end, and it would help to have it split further up, to help users reach a part of their engine block or chassis more easily. Also, I highly recommend addition of diagrams. There are words saying “connect wire to engine block or vehicle chassis, not sheet metal or fluid lines” but some of us need an illustration of what is a sheet-metal body part vs the vehicle chassis!Once connected to the engine, I turned my back on it just in case, to plug in the “wall wart” (credit to Mythbuster Adam Savage for that term) and the light turned steady red! This was encouraging, since when I had tested it earlier by plugging it into the wall with no connections made, it blinked red. So I was confident I did not have a defective wall wart box.6 hours later, the light had turned blinking green, and 6 hours after that, it had turned steady green, which the manual says is the perfect state to leave it in for ‘drip feed’ of electricity to keep the battery operable while not in use. So I am perfectly satisfied!Our car’s battery was diagnosed by a mechanic as “being on its last legs” anyway, so this comparatively cheap product, for 2 months of use only, is perfect for our needs. I’d recommend anyone with a really expensive car or battery that needs storage for 6 months or more do a bit more research and spend a bit more on it.

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I bought a new battery six months ago, so I was pretty annoyed when the car wouldn’t start on the day, of all days, when I needed to take it to my mechanic for the state safety inspection.I jumped the car and took it down. I thought the drive would have charged the battery, but my mechanic called a few minutes after I left and asked if I had trouble starting it. He jumped it and did the inspection, including confirming my alternator was working. When I picked up the car, he suggested I replace the battery under warranty because his trickle charger wouldn’t charge it.I am far too lazy for that, so I took it home and connected it to this little charger. It clicked on instantly without any fuss (I didn’t even need to use this charger’s override mode). I bought the tiniest one so it’s a slow charge, but a couple of days later I put the battery back in the car, and it was as good as new.To be fair to my mechanic’s charger, by that time I connected this one, I had driven the car again and my lithium jump pack had been connected for several more hours, so maybe one of those actions had given the battery enough juice to be worth charging. Still, the fact that he tried several times and that I had no trouble puts this charger on my “nice” list.

The manual states the 2X4 charger can “maintain” any size battery, it’s that simple. The 40Ah limit has to do with charging. The more a battery goes over the 40Ah rating and also, the lower a battery’s state of charge, then the greater the chance of getting an error message. My 2×4 is maintaining 4 – 100Ah batteries. Placed all on the charger in a high state of charge and within 24 hours, had 4 solid green LED’s indicating an optimized charge. Awesome!The packaging is not the best where mother earth is concerned. Its includes 4 different national power cords so use 1 that’s needed and trash the other 3, that is a disgusting waste of copper and the energy used to manufacture and transport. The manual appears to cover every known world language so its heavy for its size and again a waste of material and energy so really, why not have a paper manual for the 4 most spoken languages; English, Spanish, Mandarin (Chinese), and Hindi (Indian) and have the rest available on line. Packaging has foam where corrugated cardboard would suffice so, it would be great if they could make that change. On the plus side, the cords and clamps are bound with twist ties versus in plastic bags. Lastly, I like the charger!

The container comes with an assortment of European power cords. What a waste! This is not a travel kit, it goes into a shop or garage and stays there, in one country. The power cord could be a couple feet longer. The extension cord on the low power side is well made. However, it should have a lock function or be more difficult to disconnect / pull out. The rather fancy soft transport case should have been made to be able to leave the power cords attached! I am very disappointed that an internal fan was required too cool the unit. This is a point of failure, especially when the unit is used on the go, occasionally dropped or handled somewhat rough like normal in a shop. It should be ok if mounted to a wall or kart, but oily dust will eventually clog the darn fan, requiring cleaning. The fan is noisy, but that should not present an issue in a garage or shop. I do like the post clamps. They grip and stay.

After having used it on one battery charge will say all this in complete honesty of a review. For one charge is completely simple just attach to battery that’s already attached/plugged in on the car’s system and will charge. Works fine with charging as noticed afterwards did notice a difference in how car did do starts ups much faster/quicker with noticeable power. You can say as if it did increase in performance that is in electrical power. I say this as a car that was used did have lot of electrical power usage in the daily, more or less. For was used on my car’s battery (Scion tC), it did have lot of different attachments like: new speakers not stock, interior lighting added, new internal dome lights in the front and back seats, with new front lights, and having added fog lights. All this you can say was and is using more power than stock or than an average car least of that type/year/model of a version car. Reason I had thought and did buy this product for its good have a charger keep the battery always in top set capacity/charge least check it every once in a while or forsure if having lot of power usage like this. Not to mention if you use your cars power to charge devices or like your phone/or hearing daily music in your car’s speakers. Plus batteries do age as time progresses. Way to possibly save money by keeping battery healthy and charge least saving some time and money.Now for the bad, I had assumed this was a also repairing feature as did say somewhat in the readings but apparently only for the 5A and 10A version. For got missed communication in the ad description of the product. Along with the other bad con of this product as it is simple… too simple. Which may be good but too simple as you won’t know how dead of a battery your car is if it’s completely dead/waste of trying charge it. In how it only has a single light being red or green in pretty much if needing a charge or fully charged. This going hand in hand being bad as it won’t automatically repair… for you need the more expensive and better product of their’s that does have the feature “repair mode” on their again the 5A and 10A version of theirs. Now for the charge on how long it will take, oh may god, all day for it to fully charge enough to turn the light green. For as I remember this when I used it on a battery that was fine on a car used semi daily (Scion tC); did the charge take like forever pretty much all day. So if you are to get this be prepared not used that car or battery. For my charge of a Duralast Gold (130 Reserve Capacity/700-875 Cranking Amps) battery not more than say a year or two old. Did it take pretty much all day. For I remember setting the charge mid to right after afternoon time and not being fully charged until nighttime. Taking least if I recall correctly, more than 4-6 hours at least; and on a not dead/slightly under full capacity battery one is to think how long a low battery take or big battery. Possibly all day, meaning as in morning til night or you can say… 9 til 5. Heh heh corny joke. But yes, this may take a while reason had to return and buy their 5A version. 1 No repair mode/repairing, 2 Charge take too long, 3 (Little nitpick somewhat/personal opinion) Not showing progress of battery level; Only showing pulse/flashes in red and green pretty much only 2 level if charging/need charge (red) or charge think was 75-100% green pulse/flash.So will advice possibly best get a 5A minimum (has repair mode/shows progress/faster charge) or a 10A (same as 5A but with added: supply charge, fastest charge, and chargeable for a 6V even) if willing spend little more, save an hour or two in charging and if having need a charger for a big battery/okay spend couple more bucks.