Re-celling Advice Please

[Gavinskii]

Hi All,

I have a Wisper Works 805FE (a little aluminium folding bike with 16" wheels and a rear hub drive).

It's not been used for a long time and I am looking to recommision it.

Starting with the battery - the battery box sticker indicates that it is a 25.9v 8AH Lithium battery. Having charged it for 12 hours I took a reading from the output and it was showing a mere 4.9v :-(

Q1) As the bike is quite old is it worth having someone check if any of the other gubbins inside the battery box has failed, or should I just look at getting a re-cell?

Q2) Could anyone advise if it is possible to up the power and capacity a bit with this hub motor? If so any recommendations on a sensible level?

Q3) I really don't want to chuck too much money at this as the bike is old and won't be used too much - therefore who would you recommend takes on the recell?

Thanks in advance for any assistance.

Gavin

 

[Wicky]

http://ebikebatteries.co.uk/recelling/

1A Gateway Mews, Ringway, London N11 2UT

Tel: +44 (0)208 361 1790

Email: info 'at' bga-reworking.co.uk

 

[Nealh]

It will more then likely only be the battery that is wanting.
Not 100% sure but think some Wispers have a sleep mode on their batteries, once woken up it may be fine. David from AMPS is frequently on the forum sure he can give you a more definitive answer.
If recelling is required then you can use any ah capacity you like, yours is likely a 7s battery so 29.4 max charge. It is possible to go up to a 8s/30v or 9s/33v set up for a bit more power however the controllers internal capacitors would need checking, then the other issue is buying another charger so about £60 odd for that.

if you are pretty handy at opening things up then we can help you to do some simple voltage checks inside the battery and possibly try to see if any life can be resurrected. All it would need is a bit of patience and if it works would prove to be free.

 

[Deleted member 4366]

You could increase the battery to 36v for more power. Most 24v controllers work OK at 36v. If it blows, a replacement doesn't cost much.

 

[Gavinskii]

It will more then likely only be the battery that is wanting.
Not 100% sure but think some Wispers have a sleep mode on their batteries, once woken up it may be fine. David from AMPS is frequently on the forum sure he can give you a more definitive answer.
If recelling is required then you can use any ah capacity you like, yours is likely a 7s battery so 29.4 max charge. It is possible to go up to a 8s/30v or 9s/33v set up for a bit more power however the controllers internal capacitors would need checking, then the other issue is buying another charger so about £60 odd for that.

if you are pretty handy at opening things up then we can help you to do some simple voltage checks inside the battery and possibly try to see if any life can be resurrected. All it would need is a bit of patience and if it works would prove to be free.

Thanks Neal - the battery is split and I have a basic avo meter which I am not overly comfortable with using - but very willing to try!

 

[Gavinskii]

You could increase the battery to 36v for more power. Most 24v controllers work OK at 36v. If it blows, a replacement doesn't cost much.

Thanks Dave, that sounds good.

 

[Deleted member 4366]

Firstly, you can't get a shock off this battery, so don't worry.
Set the dial to 20v. The top sliding select needs to be set to DC volts. DC is the one with only straight lines. AC has the curly line.
The symbols in the photo are too blurred to see which is which.

On the bottom end of the pcb in your photo, you can see a line of 8 holes, number zero to 7. Stick your black probe in the hole marked 0 and the red one marked 1. Record the voltage. Repeat using holes 1 and, 2 and 3 to 6 and 7. Show us the seven results.

Be careful not to let your probes touch each other while they're in the holes. You'll get a spark, but no harm will be done unless you keep them touching.

If you don't get a reading, try twizzling the probes in the holes to get a better contact.

 

[Gavinskii]

Firstly, you can't get a shock off this battery, so don't worry.
Set the dial to 20v. The top sliding select needs to be set to DC volts. DC is the one with only straight lines. AC has the curly line.
The symbols in the photo are too blurred to see which is which.

On the bottom end of the pcb in your photo, you can see a line of 8 holes, number zero to 7. Stick your black probe in the hole marked 0 and the red one marked 1. Record the voltage. Repeat using holes 1 and, 2 and 3 to 6 and 7. Show us the seven results.

Be careful not to let your probes touch each other while they're in the holes. You'll get a spark, but no harm will be done unless you keep them touching.

If you don't get a reading, try twizzling the probes in the holes to get a better contact.

Thanks Dave - readings are

1 0.52
2 3.04
3 4.36
4 7.32
5 8.46
6 9.64
7 10.9

 

[Deleted member 4366]

Totally shagged!

 

[Gavinskii]

Totally shagged!

Thanks for confirming Dave, looks like I will need to give Jimmy a shout

 

[Gavinskii]

Just thought I should advise that I got a really good service from Jimmy @Insat International who re-celled my pack with a Boston cell set up and new BMS.
I’ve now charged the pack up and unfortunately there are no signs of life from the bike. I attach a couple of photos and wonder if one of you lovely people could provide me with some simple instructions as to what to test with my basic meter to isolate where my wiring / component fault might be.

 

[Nealh]

You need to confirm that the battery has a voltage out put reading and it has been switched on.