Saggy battery -Oxygen S- Cross CB

[DBye]

I've noticed significant sag from my battery recently. The bike is around 2yrs 4months old and has had a hard life. I'd estimate 7000 miles of commuting in Sheffield (odometer unreliable as had new conteollco last year). Today the display showed the battery voltage as over 41v hot off the charger, this then sank to 34.0v about halfway through my commute. I paused and watch this then rise back to 35.8v. I can mitigate it by using the bike in normal rather than power. But is this a sign it is time to give Jimmy at insatiable a call?

Also how does that work because surely he can't quote until he has the case in front of him and can see how many cells will fit?

 

[gray198]

might be worth a visit to South Yorkshire Electric Bikes in Rotherham. I don't think their replacement prices are too bad

 

[wheeliepete]

Sounds like your pack has done pretty well. Give Jimmy a call and maybe e-mail a pic of your battery case, I think he will be able to give you options from that.

 

[Nealh]

Most likely it is 5p 10s so 50 cells.
Buying a replacement from Oxygen will most likely give you the same or similar cells, with Jimmy he can offer you pucker cells like the superb Panasonic GA or Samsung 30Q. GA for more wh/range & 30Q for higher amp draw though GA is no mug of a cell and is said to be 12a capable according to Mooch on E-cigs forum, he does hundreds of unbiased /independent cell tests.

 

[DBye]

Thanks, spoke to SY Electric Bike. They quoted £440 for a 13aHr new battery. Called insat, Jimmy is away until later this month but will discuss options and approximate cost, then if I'm happy they will collect the battery, recelling, I then pay, and then they return.

So, question for now is do I use the dreaded bus or risk the bike with the battery as is! Last night battery was 38v hot off the charger before cycling home, this morning it was back up to 41.5v.

 

[Nealh]

A jimmy recell will be about £120 - 150 cheaper.

 

[DBye]

So I went with Jimmy. I boxed up the battery, they sent me a shipping label and it was picked up the next day. Jimmy re-celled it to 17.5 Ahr and also identified a problem with the BMS which had been limiting current draw previously, so had a new BMS too. Jimmy also checked my charger to ensure it was functioning correctly (which it was).

As the BMS appeared to be faulty, Jimmy checked the original Samsung cells which were still healthy, although down to around 9Ahr from 13AHr. As I use the bike everyday for ~28 mile round trip I had it recelled anyway, rather than risk having to send it off again. Total cost was £400 inc VAT & P&P.

Riding the bike today it feels like new and has more poke on the hills, presumably from the BMS now no longer prematurely limiting current draw.the new cells. Either way, very happy!