Lithium 4s 0.8A, TM-471, 8-step 12.8V 0.8A sealed battery saving charger & maintainer

I also have the larger 5A Optimate lithium charger, and this one does just as well, albeit a tad slower on larger batteries due to the lower current rating - less expensive but certainly no less capable! Like all the Tecmate-Optimates, you can connect and walk away without setting anything knowing that you'll get the absolute best charge safely. Not often considered compared to other chargers is all the pre and post charge testing that gets done on a continuous basis, specific to the lithium chemistry. Something that lead-acid based chargers don't do properly with lithium. Close, but no cigar. Note that "walk away" does NOT mean leave for work or go on vacation. NO battery of any chemistry under major charge should be left unattended. Having said that, while I own and have seen the similar looking, lead-acid based "Optimate 2" do an OK job on charging lithiums due to it's overall simplicity, the lithium specific TM471 is a far better charger than the Optimate 2 for this purpose. You get lithium-specific voltage tracking, testing, low-voltage recovery, AND cell-balancing pulses near the end of charge you don't get with the lead-acid based Optimate 2. All voltages tracked accurately with my Fluke 87V monitoring the charge process, just like all my other Optimates. That's why I own more than one. :) The extensive post-charge testing (if you ALLOW it to actually do a 12 hour long-term test) can give you an indication of problems long before bike issues leave you stranded. I'm a battery geek and can quickly see through hype. No hype here. It is so refreshing to actually see a product do exactly what they say it does, and openly discuss it in the manual.

Put a lithium battery in my Kawasaki Mule; big difference in starting. Bought this to make sure it starts every time, no matter how cold or how long it has been sitting. Solid product that protects your battery investment.

Charger saved the EarthX ETX680 on my Sportcruiser airplane. It was discharged to 4.1 volts and several attempts to recharge it using a couple of different EarthX approved trickle chargers failed. I tried the EarthX recommended approach of momentarily hooking a good 12 volt battery in parallel with the trickle chargers to no avail and had resigned myself to having to replace the battery. After reading the reviews, I ordered the Optimate 4s .8A charger, which was received the next morning. I love this charger. It's totally automatic. Just connect and it interfaces with the built in BMS protection circuitry on the battery and goes into Save mode if the battery is more than 50% discharged. A light tells you whether it is in Save mode, charging, or fully charged. Unfortunately, the lights are not labeled, so I used my label maker to mark them, which is no big deal. This charger just works!

A VERY GOOD BATTERY TO BUY FOR YOUR MOTORCYCLE!

Incredible! This charger restored my presumed-dead battery. I accidentally shorted and almost fully drained an Antigravity 8-cell battery to a point where it was reading 2.9 V. According to Antigravity, you should never let your battery go bellow around 10.0 V or it will be irretrievably lost. If a battery is questionable at below 10.0 V, then it surely must be dead as a door nail at 2.9 V. Anyway, I was about to buy into Antigravity's pitch and buy a new battery when I read a few excellent reviews about this charger on amazon.com and bought one. It comes with everything you need and is 100% plug-and-play with nothing extra needed. It has several different modes and stages of charging batteries. When I connected it to my "dead" battery, the SAVE light came on and then after about 6 hours the CHARGE light came on and a few hours later my battery was fully charged reading 13.3 V. Five days later, the battery was still reading 13.3 V and it's cranking power seemed perfectly restored.

Excelent

On my new street bike, the charger indicated the red ‘!’ after charging, yet it is likely due to normal draw down of a key FOB bike with the latest electronics. The bike is always sensing for the FOB signal. Probably not a red alert!

I have been into motorcycles for many years and that means I have been into motorcycle batteries a long time too! Lithium batteries are far superior for motorcycles. All aspects are enhanced-- less weight, no liquid acids, mount in any orientation, smaller yet more powerful, hold a charge and last much longer. Charging is different for Lithium and their are many motorcycle battery chargers out there for them. I have tried the upper tier of chargers and OptiMATE is a solid A+. The most sophisticated of the bunch and exceedingly easy to use. They have been in the business for a long time.