My BMS quit. I think. Something quit

[mvadventure]

Batteries: Aten Energy LiPO4, 48 volt, 20 AH

OK, here is the deal: Today, in the rain, a light rain, a mile from the house my battery quit. Prior to quitting the battery was reading >52 volts and had been used only 15 miles. When everything stopped I glanced at the watts up and had dropped to 22 and then was dependent on how fast the front wheel was turning. As I slowed down the voltage dropped accordingly.

Since I don't use a fuse I immediately checked the connections and all were watertight and in good condition. Turning the key on and off allowed the red throttle light to come on but that's all, not even the watts up meter. So, much to my chagrin I pedaled home. I didn't like it, the bike is heavy, it was raining, I was wearing LOTS of rain gear and very tired.

Once home and in a dry garage I looked at the battery and all appeared OK. I pulled the connectors off the red and black leads from the battery and got 18.6 volts, the black lead comes out of the BMS. The battery tops are covered in a piece of Chinese bakolite or something to which a solid state thingamajig is taped with about a bunch of wires going into it through four multi wire pins, all from the battery. I removed the top of the thingamajig and sure enough there is a circuit board, some stuff that looks like toothpaste smeared over part of it and a couple pieces of metal (aluminum most likely) that had stuck to the top of it. Despite the toothpaste looking stuff everything looked OK, nothing burnt but I'm not sure about those pieces of aluminum so I merely put it back together the same way it came apart. Then I checked each cell and all was well and put my meter back on the red lead and directly on the negative lead and got 52.6 volts. So, the battery itself is good.

Putting a meter on the charger connection gives me 18.6. A thorough visual inspection shows no broken or burned wires. When I reconnected EVERYTHING the red throttle lot comes on, the controller (48 volt 40 AMP) light comes on but the watts up remains blank and there is not sufficient power to get the wheel to turn.

I have not taken all the wires from the controller to the wheel apart as I don't think the problem is there. I think it is in the BMS and am searching for opinions and ways to get my bike running again as I need it Monday. Had this happened yesterday I would have been screwed as I was 15 miles away at one point. Not even Lance Armstrong can pedal this beast 15 miles.

Calls to Aten Energy have yet to be returned but in their defense it's only been a couple of hours and it is Friday evening on the East Coast. Who knows what time it is in California.

Mike

 

[mvadventure]

RESOLVED

Ten minutes after I posted my problem Zane of Aten Energy called and spent a half hour on the phone with me. It is the BMS and it's a balancing problem and can be reset and he gave me instructions on how to do it but we're simply going to change to a charger with a built in BMS.

In the meantime all I have to do is d/c the bms and do a little rewiring and all will be well 'till the new charger gets here. When it does I will have to rewire the pack which will take a few minutes to accept the new charger. I forgot to ask him if it will be charge any faster but with the range the batteries give me it really doesn't make any difference.

The unusual thing about dealing with ATEN Energy is that Zane actually thanks me for using the battery and helping to discover any little glitches. It's kinda like a beta situation but with the admirable service I've gotten I got no complaint. Yesterday for example was 8.6 miles, 16 miles and then 11.4 miles, all on one charge.

Mike

 

[Joey]

"Re: My BMS quit. I think. Something quit."

I'm glad you got the problem resolved. I was going to suggest that you eat foods with more fiber.

-- Joey

 

[PJD]

Mike,

By the way a few weeks ago, I got a confusing phone call from Zane, saying something about battery packs being held up by US customs, but also it became apparent that he seemed to be unable to provide me with just bare cells for building my own pack with my own BMS. I left open the possibility of buying a pack form him open, but he never got back to me.

I have decided to buy Thundersky's instead. They can be more easily fit in my scooter battery boxes anyway.

 

[Link]

"Re: My BMS quit. I think. Something quit."

I'm glad you got the problem resolved. I was going to suggest that you eat foods with more fiber.

-- Joey

Ah, ha, ha, ha, ha! :lol:

 

[mvadventure]

PJD,
When I talked with him last night he indicated he had quite an inventory. He sounded like he had been doing quite a bit of commercial work and mentioned a few projects. I don't think at this time he appreciates the potential of the bicycle/scooter market. It's probable that, like me, he sees one only rarely I did see an electric scooter in Daytona this morning though.
Mike

 

[fechter]

I have decided to buy Thundersky's instead. They can be more easily fit in my scooter battery boxes anyway.

What are you planning to use for a BMS with those?

 

[PJD]

fecher,

i will be using Bob and Gary's units. Recall my question about using the LVC signal?

My SLA chargers are right at 8 amps, so hopefully it will work.

For starters, i may assemble the pack with charge-behavior-matched groups of four, with powercheqs used to help balance the groups - and a careful eye on the pack voltage as I ride. But this will probably be a temporary measure.