Need help with a battery pack.

[Synthman]

Today I received a 36v 10ah LiMn2O4 battery. It is supposed to have been in storage for a year, but not used. There was supposed to be a diagram of the charge/discharge cables but I haven't got it. Anyway I assumed the two thicker wires were the discharge ones, and tried measuring voltage. It is in the 20v region and seems very low. I tried the other 2 wires too and they all say the same.

I don't know if it is a 24v battery, if it has a broken connection somewhere, or if it just needs charging first?

 

[alfazzr]

Was it purchased from Guddies7 on ebay perchance ?

 

[Synthman]

It was indeed.

 

[alfazzr]

I think they had their heads on backwards that week. I ordered the matching one (I believe) to the one you got and it never arrived so they refunded me. Then the bottle battery I also ordered eventually arrived and was more than scuffed - it was physically cracked and broken so they agreed I could return it for a refund. Bear with me I will check my emails but they mentioned another problem someone had had.

 

[Synthman]

There's another battery listed that looks identical to the one I got. I'm almost certain it is a 24v battery as the two readings I got were 19.5v and 20.6v.

Looks like it will have to go back and I'll have to order from BMSbattery instead. I can't believe this!

 

[alfazzr]

Is yours like this one ?
Electric Bike battery 36V 10Ah Lithium | eBay

I thought he had said in an email about someone getting the wrong voltage battery but I cannot find it now - perhaps I dreamed it !

 

[jerrysimon]

Isn't this these guys ?

Electric Bike Sales - Electric Bikes, Repairs Conversions

Regards

Jerry

 

[Synthman]

Is yours like this one ?
Electric Bike battery 36V 10Ah Lithium | eBay

I thought he had said in an email about someone getting the wrong voltage battery but I cannot find it now - perhaps I dreamed it !

Electric Bike battery 36V 10Ah Lithium | eBay

 

[Synthman]

Isn't this these guys ?

Electric Bike Sales - Electric Bikes, Repairs Conversions

Regards

Jerry

Yeah those guys.

I'm waiting to hear back from them at the moment. I hope it isn't too difficult to send back.

 

[Synthman]

Just a quick update. The seller confirmed it was a 36v battery and that the BMS shuts down after 2 hours of inactivity which caused the low reading.

I connected it to the charger and after 2 minutes it came to life, it read over 33v and I'm now fully charging it. Hopefully I'll get to test it on the bike soon after I've swapped it with my old pack. It looks like they use the same bullet connectors so it should be a simple job.

 

[cwah]

Full voltage after charge should be around 41-42V.

I'm surprised by the 1000 cycles advertised of the Limn2O4, which are known to quickly loose capacity over time.


You should do a capacity test on the battery to check how it performs. I would say that if you can get more than 270wh out of it, it's a good pack after 11 months of storage.

 

[Synthman]

It did get to 41.6v. It certainly took a significant amount of power and time compared to my old battery. I monitored the power used during the charge, nearly half a unit (0.45 vs 0.26)

Unfortunately I'm not capable of installing it in my battery case. My first issue is that I cannot solder properly. I thought I could get away with disconnecting the leads and plugging the new ones in therefore avoiding soldering. I cannot disconnect any of them because they won't move. Furthermore it seems there's only 3 leads coming out of my old battery. Theres 4 coming out of the new one.

I can see the discharge negative from my old battery connects directly to the socket, as does the charge negative. The positive discharge goes from the battery to the fuse, then to the discharge socket and also another wire goes to the charge socket.

Also, I thought the colours were confusing. Red and black on the discharge is simple. On the charge it is pinkish and orange. Indeed on the old battery the negative charge lead is also orange.

 

[Synthman]

Still haven't tried it out yet. I was going to go to Maplin and look for connectors, can't be bothered now and I'll never find what I want anyway. I'm thinking of ordering a pack of bullet connectors and a C17/C18 socket. That way I'll be able to connect the battery directly to the bike and strap it down on the back. Do you reckon I can screw that one up? Of course so I won't bother!

At least I saved money on the battery, I will have to use the savings to pay someone to install it in the case for me. Anyway I 100% guarantee that when I have to make my 8 mile trip tomorrow, that I'll be doing it on a practically 5 year old XH370-10J battery, and it will cut out at least twice on the way and give me a maximum range of 9 miles.

Why the **** didn't I buy a ****ing Vespa. I know they're complicated but at least there's people to deal with that, and the parts are easily available.

 

[cwah]

What's the issue with soldering? Is it a problem to stick it with the battery tab?

Also, what do you need for the case? Maybe you can create your own case for cheap, I had my own polycarbonate box case with vibration foam for 20£ here

 

[Synthman]

Well that's an issue I had on my old battery. However I've had another look and I now know what I need. Just one bullet connector and some more solder just in case. I'll pick those up in Maplin tomorrow and swap the pack when I get home.

I'm reusing the same case. I'd love to buy a spare case and put my old pack in but the only place I found to get it from is Australia, the postage is more than 10x the value of the case!

 

[Synthman]

I've fitted it now. I hope it is secure inside the case. I used some of the foam that the battery was delivered in to pad the bottom and sides, duct taped it into the case and put a few blocks of wood on the side to take up space. Tomorrow I'm going to see if I can do a 14.5 mile journey on it.

 

[cwah]

Nice job.

Looking forward to heard about the capacity of your pack.

 

[geostorm]

THEY ADVERTISE (some of what you say, it seems to lacks confidence in them )..... a testing recell service for i believe £350 , as anybody you know had any decent results or any comments to offer.

(some of what your saying, it seems to lacks confidence in them )

 

[Synthman]

I've tested the battery. When I got it last week I attached it to the charger but when the green light turned on I didn't leave it plugged in for a for a while longer. So today it was only 41.2v when I started my ride.

It coped with my test journey of 14.4 miles no problem. The battery level lights didn't drop even when going up hill. The bike was quite powerful and fast. When I got home I was surprised to find it was still over 37v so I went round the area for a bit and did another 1.5 miles before it cut out near my house. So I'd say it was pretty much 16 miles. I'm very happy considering the total cost! It's much better than the one that came with my bike originally.