Battery failing, Worth a try ?

[shinybryan]

Hi there, i'm new to electric bikes, having just got a second hand Ezee Sprint on Ebay, its in fine condition with only 700 miles showing on the meter, which the seller assures me is correct, and except for the battery I am very pleased with its performance.
The Electric Transport Shop in Cambridge have done a "Refresh" but the LED lights still go to red after a couple of miles and dont recover till I recharge!.
My dillema is, do I try one of the Powerstream battery chargers with the discharge function and persevere with regular charge and discharge cycles, hopeing to gradually bring it back to life, or do I just bite the bullet and go for Li Ion plus a new charger ?

any help would be much appreciated.

has anyone got a Sprint Manual on PDF perhaps ?

many thanks, Bryan

[flecc]

Hi Bryan. I gather you mean it's an NiMh battery, and the Sprints haven't been sold with these for a long time, so it's possible the battery is dud through being left idle for too long without charging.

However, if an NiMh battery isn't used for a long time, it can sometimes be recovered by conditioning again as one does with a new battery. That's done by fully charging, then using it on the bike until cut-out or near empty, then repeating that two to four times.

If you have already done that two or three times without improvement, it's the battery that's failed. In that case it means a new NiMh battery which I understand Cyclepoint can still supply if you ring them, or as you say, a new Li-ion set of charger and battery.
.

[shinybryan]

Hi Flecc,

Thanks for your prompt reply, yes I think you are right, the bike had been standing for a long time and I dont think the owner had bothered, (or understood the need ) to keep the battery charged, or for that matter keep the tyres hard as they were also soft on arrival. Having tried the refresh recharge and run till cutout route I think I will go the whole hog and plump for a lithium battery and charger as this seems by your various tests and comments the long term answer. Thank you again for your sound advice.

Regards Bryan

[Danny-K]

Originally Posted by shinybryan

Hi Flecc,

Thanks for your prompt reply, yes I think you are right, the bike had been standing for a long time and I dont think the owner had bothered, (or understood the need ) to keep the battery charged, or for that matter keep the tyres hard as they were also soft on arrival. Having tried the refresh recharge and run till cutout route I think I will go the whole hog and plump for a lithium battery and charger as this seems by your various tests and comments the long term answer. Thank you again for your sound advice.

Regards Bryan

Have a similar query to Brian, but the Topic button won't allow me access. I have a chance of a secondhand bike. The battery, a Lithium Polymer battery – 26V 10.5Ah, was new 4 months ago and has been charged just once in that time. The rest of the time, obviously, left standing unused. The owner should have charged it once a week if left unused but he hasn't.
So, haven't even seen it yet; but what do you think? A quarter of a year - serious deterioration, or recoverable - what does your experience tell you? Anybody?

[flecc]

Actually it's normally only necessary to recharge lithium every 2 months or so.

In fact most lithium cells don't self discharge at all, a characteristic fairly unique to them, but the control and balancing circuits built up batteries contain create some small leakage, hence the need for occasional charging.

Temperature also controls the loss of capacity over time, and it's only about 2% in a year at zero degrees C, so much depends on where that battery has been kept, in a cool room or a baking hot garage making quite a difference.

So the battery could still be good, and if a charge gives a reasonable range its going to be perfectly alright. On balance it's probably going to be ok, but I can't be more certain without knowing at least the original quality and the exact circumstances of storage.
.

[Danny-K]

Thanks for that reassurance Flecc. I was subconciously discounting the price of a new battery from my offer. I've been around bicycles and motorbikes all my life, but pedelec's and e-bikes are new terrtory for me, so thanks for the guidance.