Cheapest Lithium Challenge: Cheapest Battery on Amazon

Skip to the 5 min mark. Trust me.

Another concern, particularly in marine applications.... the battery case needs to be COMPLETELY sealed from moisture. I bought a Chinese 36v 100ah battery direct from China... it was cheap, about $1300 delivered, with a 40-amp charger. It worked great for several months, then failed to charge. I decided to peel the cover off and inspect. The warranty period was over, I wasn't going to ship it back to China for evaluation, so I had nothing to lose. When I got the cover off, I found the copper plates that were used to connect the cells had corroded, and corrosion on the BMS itself. The battery had never been submerged, but in the bilge of a boat, it's certainly around moisture, but never standing water. I tested the cells, and all seemed to be fine. So, I replaced the solid copper plates with nickel plated plates (E-bay), and sent photos of the battery to the company that manufactured it. They were kind enough to recognize that water vapor had caused this damage, so they sent me a new BMS and a new top for the battery, which I was very careful to epoxy back on around the entire mating surface. It's been 2 years now, operating without a hitch. So, looking forward, if I purchased another "cheap" battery for a marine application, I would look for no options like USB ports, or cover those openings with silicone sealant or something to keep out water vapor. I'd also consider sealing around the outside where the cover mates to the bottom of the case.

Thanks for the info. It was pure serendipity, er, the algo, that had your channel pop up for the first time last night for me. I just started studying these batteries last week and have already learned some crucial information thanks to you. Information that pre-saved me money because of my ignorance. Just throwing this out there for people like me in colder climates---there are battery blankets (electric-powered) that many motorists in particularly cold winter areas of Alaska use and I'm quite certain they could be useful in preventing damage to batteries in a chilly battery charging situation. Cheers!

Thanks for making this video and sharing your knowledge, it is much appreciated. Thanks again

Great job Clark, love how you think. I see the comments about buying much more expensive batteries and I get it. If you were crossing oceans or backing up something critical, I would agree, but spending good money on a temporary situation is extravagant.

Thanks for the review, looking to go lithium in my boat this helps a lot.

Great video, and info. Im upgrading to Lithium from lead acid on my sailboat, and have been searching for something in the "middle of the ground " type deal, and now I have something else to further research. I have watched some of your other videos, and definitely will subscribe. Thanks.

Great post Clark. I appreciate all the information you are sharing here. I always enjoy tuning into your newest post. 💛 🌴⛵️🌞

Thank you Clark for this happy and positive video :-) This video has reminded me to check the charging on my sealed lead acid battery for my HF radio. It'll almost be done. But now I am off to water the baby lettuce. Cheers :-)

Great video. Thanks. That's a sweet affordable turnkey solution, but as a full-time RVer I was looking to replace the 2 golf cart batteries that were located under the steps of my motorhome with the highest capacity LiFePo-4s that would fit in this limited space. We decided to build our own 560ah LiFePo-4 battery bank with a 330amp Heltec BMS (to start the 5,500-watt onboard generator) and a 5a active balancer for under $1,500. We built our 12v battery out of 8 grade "A" 280ah LiFePo-4 prismatic cells having an 8,000-cycle projected life at 80% DOD or 6,000 cycles at 100% DOD. This means that if we cycled them 100% every single day, 365 days a year, they would last over 16 years! So, they're obviously going to wear out from age before they wear out from cycling as we only use 15-20% of their capacity daily giving us enough reserve capacity for several days of bad weather before we have to run our generator for charging. They even saved us 35 lbs compared to our old FLA batteries and have over 5 times their capacity. Of course, it's not just a drop in like the pre-assembled PUPVWMHB battery you featured. We top balanced the cells before we assembled the battery, though they were all within a tenth of a volt when we received them. This was probably unnecessary as our 5-amp active balancer would have surely done the job, but spending this much money, we wanted to do the job right. They were economical too. $1,500/560ah = $2.68/ah vs $299/100ah = $2.99/ah for the PUPVWMHB battery. There are cheaper "B" cells available from China that are typically rated at 3,500-4,000 cycles, but we decided to spend a little more to get the higher rated cells shipped from a California warehouse, so if we got a bad one it would be easier and quicker to return and get a replacement. Happily, this wasn't necessary. We insulated the battery compartment, cut a 1" hole in our step risers and installed a tiny computer CPU fan to circulate just enough room temperature air into his compartment keep this space at close to room temperature, so we don't have to worry about the BMS shutting down charging if they get too cold - or their life reduced from getting too hot.

Thanks for the link. It will be a while before I install the electrical system in my C-25 bare hull refit. These look like what I need to get ready for sea trials.

Love your work, Clark!

Thanks for the no nonsense non-tech breakdown on this battery. It looks like it might be a good candidate for when I set up my home backup.

You made up my mind on what type of batteries to install in my RV. Was thinking about lipos, but we'll be in cold climates sometimes. I'll stick with lead acid for now. We don't boon dock much. But we're seriously thinking about chasing the warm weather. Then they'll be great. Excellent video.

Thanks for reassuring me, I bought 2 "cheap ones" from Amazon too, 180 AH each. I'll hook them up to my BBMS in the next months and will report, how they worked for me. They claim to be automotive grade as well and now I know what that means.

I discovered your channel this morning. I've been following a few of the better known sailing channels for the last 2 to 3 years. I am surprised that I haven't come across yours until now. I think the tie-in was the LiFEP04 battery review. I also build my own battery backup systems. Great video. I appreciated your take on the grading of batteries. It is an interesting viewpoint to consider. You are not right or wrong. Much like many topics, it is another ambiguous topic which seems to have no valid data source to demonstrate definitive proof one way or the other. What some have said is only an opinion. Unless there is demonstrative proof, it is simply an opinion. Like many, I am also leary of the claim of low temperature protection. But you are correct in that if you don't live in a climate necessitating below freezing charging, you don't need that feature. I searched for other YTube videos that reviewed this battery. You seem to be the first. I would like to see a few more YTube reviews, preferably with a cold temp charging test before making any decision. I will definitely check out your other videos now that I have found your channel.

I’m hoping to be building a system later this your, and this episode has allayed some of my concerns. Thank you so much

For my hybrid car, a 36 to 50Ah battery works just fine,and is cheaper. I do run a 2 way diode to lower the voltage by approx 0.6V, because the 14.4 charge voltage triggers the bms fron charging it (I think the car charger sends 15V pulses to determine how full the battery is, shutting down the bms). The diodes are like up to 1200v or something, some people ran them with 180A peak, 50+A continuous.

I enjoyed that as a “ nontech “ and limited funds person, thank you . And for those that have to have all the I s dotted and the T s crossed tested to the Nth degree destruction and 110 % guarantees, just buy the big dollar version and don’t bother watching. Cheers Clark .

Excellent lesson! TY.