Faulty battery ?

Saracen

Esteemed Pedelecer
Aug 24, 2023
532
61
I have a Hailong 36v battery, in fact I have 2 bikes so 2 batteries on my 250w BS01 motor.

I went out just now and the bike kept cutting out anything from 10 yards to 30, switch battery off when cycling, back on, switch bike on and off again another 10-30 yards.

SWAPPED battery, appears to be OK ?????

Battery was 65%, two green bars charged to at least 65%.

Any advice appreciated.

ALL upgrades were undertaken professionally by Cogs-Y-Gogs Wales


battery.jpgIMG_1617.JPG
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
6,209
2,925
Telford
Is it still under guarantee. You haven't had it long, have you?

The only way to diagnose problems with batteries like that is to get your meter and screwdriver out, open it up and start measuring.

You can get some clue from the LCD. If the bars go down before it cuts off, it's a cell problem. If it just switches off, it's probably a connection issue, unless it has a temperature sensor that's faulty.
 
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thelarkbox

Esteemed Pedelecer
Aug 23, 2023
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328
oxon
Investigation will probably require you to start by checking the voltage of the batteries cells which would void any warranties outstanding, so if still under warranty i would request advice from the supplier to start with..
 

Ev_

Just Joined
May 24, 2024
4
0
I've literally just had exactly the same problem with my 52V 13ah Hailong battery as you've described. I've posted asking for suggestions / sources of reputable UK based replacements (too many battery fire horror stories to mention!) but my post hasn't been published yet, so I'm keen to see what the outcome of this query is, as well as any suggestions for battery replacement sources that can be trusted.
 

thelarkbox

Esteemed Pedelecer
Aug 23, 2023
1,054
328
oxon
I've literally just had exactly the same problem with my 52V 13ah Hailong battery as you've described. I've posted asking for suggestions / sources of reputable UK based replacements (too many battery fire horror stories to mention!) but my post hasn't been published yet, so I'm keen to see what the outcome of this query is, as well as any suggestions for battery replacement sources that can be trusted.
While waiting for your own post to get approved..
If your battery is still under any warranties. same as above applies ;). chase those down first...
 

Saracen

Esteemed Pedelecer
Aug 24, 2023
532
61
I now have my other bike back from service will now swap batteries and try

I did adjust the gap on the battery as suggested thanks

Will try when the rain stops





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Ev_

Just Joined
May 24, 2024
4
0
While waiting for your own post to get approved..
If your battery is still under any warranties. same as above applies ;). chase those down first...
Unfortunately not, it's past. I think it's at the end of it's lifespan tbh, with also some rookie mistakes early on in charging and storage practices I'm perhaps lucky it's lasted this long tbh. I'm wary of imports and fire hazard batteries after recent bad press, so I need a reputable source, UK based, with a decent warranty / customer service to back up if it does go pop! Thanks - hopefully when my post goes up I'll get a few pointers where to trust
 

matthewslack

Esteemed Pedelecer
Nov 26, 2021
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1,293
When batteries are quite new and of good quality, often it is a connection issue somewhere. I'd double check all connectors in the system, at minimum disconnect/reconnect, just to exercise them all, and stand a chance of spotting anything the slightest bit imperfect.

My only issues have been with remotely mounted battery for my solar setup not being tightly enough into the battery connector. Always resolved by more bungy loop tension.