Wisper Is my Wisper 575Wh battery toast?

nigelbb

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Sep 19, 2019
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I was charging the 575Wh battery on my Wisper 705 yesterday. I wondered how much charge the battery had so pressed the battery test button while it was being charged. I saw four green bars plus red at right which is normal for a fully charged battery but then it just had one red light & started charging again.

Some hours later after the green light on the charger indicated that the battery was fully charged I took it for a spin & the battery died completely after about a hundred yards.

I left the battery on charge overnight & tried it again today with the same result. The battery dies completely after a few minutes use.

I don't know the age of the battery as I bought the bike second hand about three years ago when it was already several years old. The battery has been absolutely fine until now. Has the battery died? Did I kill it by pressing the indicator button while it was charging? What is to be done? Do I need a new battery or can this one be revived?
 

saneagle

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Oct 10, 2010
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If it charged for a few hours, it's probably OK. The only way to be sure is to measure the voltage hot off the charger and when it cuts out.

If you see the battery going down rapidly on the LCD before it cuts off, that's not good, but it may be just that your battery is out of balance, which you can often solve by leaving it on charge gor many hours after the green light comes on. Batteries often go out of balance if you don't use them for a long time.
 
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Peter.Bridge

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Apr 19, 2023
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Ghost1951

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A good thread that Peter.


Learning points for new battery users:

Use your bike /battery regularly
Never leave the cells discharged and unused
Don't store for long periods at full charge when not in use
Balance charge battery when full charge is lower than expected
Most battery problems come from chucking bike in shed over winter and abandoning it there.
 
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nigelbb

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Sep 19, 2019
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It sounds like the same issue. Maybe this is just the way that Wisper batteries deteriorate & die.
I emailed Wiper support & am waiting for an answer. The battery in my wife's 24" 705 appears to have died completely. There are no lights & it won't charge.
Fingers crossed that Wisper can do something miraculous as £1,000 for new batteries is a big chunk of cash.
 

saneagle

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It sounds like the same issue. Maybe this is just the way that Wisper batteries deteriorate & die.
I emailed Wiper support & am waiting for an answer. The battery in my wife's 24" 705 appears to have died completely. There are no lights & it won't charge.
Fingers crossed that Wisper can do something miraculous as £1,000 for new batteries is a big chunk of cash.
You don't need to spend £1000 on a battery. There are loads of alternatives for around £300.
 

nigelbb

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Sep 19, 2019
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You don't need to spend £1000 on a battery. There are loads of alternatives for around £300.
I was referring to replacing the two batteries at £500 each direct from Wisper but I see that you can find these batteries at £425 each which is still £850 for the two. https://winstanleysbikes.co.uk/wisper-575wh-rack-battery

Please can you provide the link where these batteries are available at £300?
 

nigelbb

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Sep 19, 2019
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Why two if you don't mind me asking?
Sorry, I wasn't clear in my second post. Not only is the battery in my Wisper 705 dying after 50m but now the battery in my wife's Wisper 705 (that we bought direct from Wisper three years ago) is completely dead with no lights & doesn't respond to charging. There was no warning of any problem with my wife's battery. It was working last week & had been fully charged after the last ride. We just found it dead a few days ago.
I contacted Wisper support in the hope that there was something they could do with these batteries but their only offer was 10% discount on a new battery for my wife's bike & an extra 5% discount if I bought two batteries.
 
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saneagle

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nigelbb

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Sep 19, 2019
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It doesn't look like any of those are a replacement battery for a Wisper. Even if they were Wisper compatible none of those are even UK suppliers. I'm looking for the same quality as the batteries that came with the bikes not batteries of unknown quality from some dodgy eBay seller in China or Germany.
 

saneagle

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It doesn't look like any of those are a replacement battery for a Wisper. Even if they were Wisper compatible none of those are even UK suppliers. I'm looking for the same quality as the batteries that came with the bikes not batteries of unknown quality from some dodgy eBay seller in China or Germany.
I said alternatives. If you want a Wisper battery, you have to buy them from Wisper at their price.
 

nigelbb

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Sep 19, 2019
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Why did you say that? They all fit just about any bike. If you know better, good luck.
They will fit just about any bike only if you replace the rack & rewire the bike. They are not a replacement battery that I can just slip onto the existing rack.
 

saneagle

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They will fit just about any bike only if you replace the rack & rewire the bike. They are not a replacement battery that I can just slip onto the existing rack.
Wouldn't it be better to find out what's involved rather than cast ignorant judgement?
 

nigelbb

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Sep 19, 2019
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Wouldn't it be better to find out what's involved rather than cast ignorant judgement?
What's involved is not sliding the dead battery off the rack mount & sliding the replacement battery in its place. This is what I want to do. I don't want to fit a new rack & have to re-wire the bike.

Instead of ignorant replies that don't acknowledge what is involved can you point me to an affordable replacement battery?
 

saneagle

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What's involved is not sliding the dead battery off the rack mount & sliding the replacement battery in its place. This is what I want to do. I don't want to fit a new rack & have to re-wire the bike.

Instead of ignorant replies that don't acknowledge what is involved can you point me to an affordable replacement battery?
I already told you. If you want a Wisper battery, buy one. You asked for alternative solutions, but you don't want an alternative solution. Why did you ask? It seems to me that you just want to moan about it and drown in your sorrow instead of sorting it out.