Waterlogged lite speed lite bee battery

thoroughbred

100 W
Joined
Apr 11, 2018
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225
Location
virginia
A friend gave me a damaged battery to fiddle with so I took some pics to show the internals. The history is that the bike was left outside in the elements during a rain storm which resulted in a non responsive condition. The battery was inverted in hopes of draining the water out. The top was removed in an effort to reset the bms manually to see if the battery would come back to life.

Apparently, 3 of the balance wires got severed when the top was cut off. They were spliced but when the balance connector was reconnected to the bms, the connector melted and smoked. At that point, friend abandons battery.

I accept said battery and continue what is now a post mortem investigation. The obvious and ultimate conclusion is that the battery was not rainproof. This seems like a huge weakness given how a typical Sur Ron bike could be expected to be used. If ridden offroad, one often rides in the rain. If ridden on the street, they would often be parked outside, exposed to rain.
 
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These aren't technically related to the water damage but further digging reveals that the 3 wires were spliced incorrectly. Balance wire to p group one was spliced to balance wire p group 5.
 
Your friend short circuited 4 or 5 rows of cells, but the connector "fuse" may have save him. Good chance that a new BMS will revive the battery, if the water didn't drain any rows well below 2,5V.

Good chance that even if some rows git drained lower,that they will come back, Then the question comes whether to re-use depleted cells that were revived, My vote is no if they went below the cell maker's minimum voltage, I just scrapped a battery for that reason, although I later repaired it by replacing the bad row, I tool out the cells that got depleted and they are testing perfect, but will not re-use them Not worth worrying.
 
I dived into measuring voltages coming out of the balance wires starting withe the unburned connector. I got 4 volts on the first one and the readings were slowly decreasing as I went along, down to 3.6 volts. As the notes show, I got a couple of exactly 0 volts.

This made me wonder if it is actually an 18S battery...20211013_195655.jpg
 
Here's the two layers of shrink-wrap surrounding the battery

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Beneath that is a layer of gorilla tape wrapped around the polycarbonate sidewalls
20211012_085759.jpg
 
thats why IP65 enclosures are such a bad idea, they always fail on the top, because the sun hits the top,IP44 is much better, an IP 65 enclosure can be converted to IP44 by drilling a 3mm hole in the bottom, the water can get out faster than it can get in
 
thoroughbred said:
This seems like a huge weakness given how a typical Sur Ron bike could be expected to be used.

Using a Sur Ron isn't central to its design intent. Its mission is accomplished once someone pays actual money for it. All the qualities it has, good and bad, make a lot more sense when you understand what it's for.
 
My homemade junkyardie battery has been damp and wet, from capillary action, in the layers between the cells for like.. ever since i washed and rode in the rain three years ago. Its exposed, water gets in, water gets out. Some usually stays. Through salty winters and everything. Pouch cells in a stack. Nothing ferrous.

I wonder why they make steel rust able cells... even plated they rust eventually.
 
I bought a cheap 13S-2P shrinkwrapped battery (10AH with 21700 cells) this summer, and it got unbalanced within a month. When I opened it up, the unbalanced cells were at the very end, and easy to change. I wanted to re-use the cardboard terminal washer, but they crumbled.

I have new theory as to how it got unbalanced, I remember setting it down on its end, when water came thru the garage door, It probably got wet, and caused the washers to not insulate. I tested the two cells I took out, and my tester said they had the rated AH and charged to 4.2, In the battery, they were taking about 4 hours to balance, and the BMS was get hot to the touch while balancing. New cells work fine.

Probably put 10 hours of labor into a cheap ass battery, Not buying them any more.
 
20 cells or the 2 p group of cells located at the bottom of the battery sit at zero volts.

The battery was wet enough to allow discharge of the cells at the bottom. Sort of a gentle short circuit, yikes!
 
I see a couple of issues.

1. The innards are not designed to survive any water infiltration. The bottom enclosure is water tight. The cells are wrapped in paper. Once wet, the contents have no chance of drying out.

2. The enclosure isn't waterproof. It's assembled with butt joints and sealant. The top forms a flange that traps water on top of the case if any water happens to fall there. It either leaks into the case or evaporates, it has no place to drain.

No problem if it's sold for indoor or enclosed vehicle use only.
 
The power wires exit the top of the case. Purportedly through "new waterproof" gland nuts.

Maybe packaging space under the surr ron battery cover forced the designer to modify these nuts. The nut bodies are whittled down and attached to the top cover using the gland nut. This is instead of using the bottom nut and it's rubber gasket which might actually be waterproof...

20211013_185610.jpg20211013_190101.jpg20211013_190305.jpg
 
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