Nicad battery replacemnet

[Guy Levy]

Hello, I bought a secondhand Hienzmann conversion on a very nice Raliegh about 18 months ago. Its a 500w 36v system and is about 12 years old, so not unsurprisingly the batteries are, to say the least, a little tired. I have been looking to replace them but have realised that NiCads are almost impossible to buy now so I would like some advice on what to do here please.
I originally asked Hienzmann what they would suggest and they were very helpful but also very expensive. I only have a limited budget and would really rather keep the cost below £300 if at all possible, but I am beginning to realise after looking online that this may be a bit of a tall order. The original battery and controller are all in one box that sits neatly under the rear carrier, but it looks as if I will have to abandon this set up as it appears that I will need to buy a new controller to match the new batteries which I guess will have to be Lithium Ion.
Sadly I'm no techy and having read a few things on your forum I have to admit some of the technical spec was a little over my head. I would really like some one to say, 'what you need is one of these batteries and one of these controllers', and then point me in the direction of where to get them from and tell me roughly how much they will cost. I don't know if this is too much to expect but I would be very grateful if there is anyone out there who could give me some simple answers to my conundrum.
Yours in anticipation
Guy

 

[Geebee]

Can you or a mate/ relative solder?
If so fit as many of these as needed into the existing case, sorted.
http://www.hobbyking.com/hobbyking/store/__56160__Turnigy_SC_6_0V_5000mAh_High_Power_Series_NiMH_Receiver_Pack.html

 

[jhruk]

Are you sure it's a 36v Heinzmann Ni-Cd battery? All their Ni-Cd ones I've seen that fit under the rack have been 24v, the 36v ones have been in cases that attach to the sides of the rack, with a separate controller.

German ebay (ebay.de) is a good place to look for Heinzmann battery pack recelling, with various types of cell offered at various prices. Sometimes you have to send them your case for them to fit it but I expect you'll find something suitable under £300.00 on there.

 

[Guy Levy]

Can you or a mate/ relative solder?
If so fit as many of these as needed into the existing case, sorted.
http://www.hobbyking.com/hobbyking/store/__56160__Turnigy_SC_6_0V_5000mAh_High_Power_Series_NiMH_Receiver_Pack.html

Hi,
thanks for your suggestion, if this is a real posibility then it will be a very cheap alternative which is very welcome! However I'm not familiar with NiMh's and don't know what they are or how they would perform or if they are compatible, so would welcome any views on this subject too please.

 

[Guy Levy]

Are you sure it's a 36v Heinzmann Ni-Cd battery? All their Ni-Cd ones I've seen that fit under the rack have been 24v, the 36v ones have been in cases that attach to the sides of the rack, with a separate controller.

German ebay (ebay.de) is a good place to look for Heinzmann battery pack recelling, with various types of cell offered at various prices. Sometimes you have to send them your case for them to fit it but I expect you'll find something suitable under £300.00 on there.

Hi, thanks for your prompt reply.... yes it is definately 36v and is a genuine Hienzmann kit fitted in March 2000. It cost £850 at that time...quite a price! And that's before fitting. The battery pack is a megre 4Ah and was refurbed about 6 years agoby a genuine Hienzmann engineer in Glasgow. I know all this because I was given all the paperwork when I bought the bike. Its a lovely bike and just for the sake of a new battery pack is still good for many years of use. I did contact Hienzmann and have looked at replacement batteries but they were very pricey and I only have a limited budget as I mentioned in my last post. But I'm grateful for your input and anything else you may be able to point me towards. I had no idea how difficult and expensive it would appear to be to replace a battery pack. If I had known I may not have bought the bike in the first place! But as I've got it I would like to get it going again.

 

[flecc]

The battery pack is a megre 4Ah and was refurbed about 6 years ago by a genuine Heinzmann engineer in Glasgow..

That would be Ben at Kinetics then I'd guess.

NiMh cells have many similarities to NiCad and are exactly the same 1.2 volts per cell and the same cell dimensions, whether D or C cells. They can have around double the capacity of NiCad. Unfortunately the quality of NiMh large cells is often poor since they've dropped out of widespread use in favour of lithium, so cheap ones or those from unknown sources can be suspect.
.

 

[jhruk]

Yes, that must be Ben at Kinetics. I think he's stopped doing Heinzmann now but might be worth a call for ideas.

As I said I haven't seen one of those under rack integrated boxes with 36v before and unfortunately can't find any recell options for them on ebay.de, so they must be quite rare.

If you found 4Ah sufficient there's an idea that was suggested in the April 2014 edition of atob magazine of using 36v 4Ah MacAllister power tool packs. They're sold by B&Q for £130 complete with fast charger and intended for use with their chainsaws and lawnmowers, so should be capable of delivering enough current. He used it on his Brompton and got a range of 13-16 miles.

It weighs only 1.24kg, so would be much lighter. I can't see a the dimensions mentioned anywhere so you'd have to go into a store to measure it, although even if it did fit your existing box you'd want to mount it separately so you could remove it easily for charging.

One problem using them with the Heinzmann is that the controller will lack any low voltage cut-off which is required to protect lithium batteries from over discharge. It's possible this might be built into the battery, I see it has a battery meter, but it might also be built into the appliance it's intended. for use with. This would require further investigation.

If you're interested in reading the short atob article you can download that issue 101 for 99p here.

 

[Guy Levy]

Yes, that must be Ben at Kinetics. I think he's stopped doing Heinzmann now but might be worth a call for ideas.

As I said I haven't seen one of those under rack integrated boxes with 36v before and unfortunately can't find any recell options for them on ebay.de, so they must be quite rare.

If you found 4Ah sufficient there's an idea that was suggested in the April 2014 edition of atob magazine of using 36v 4Ah MacAllister power tool packs. They're sold by B&Q for £130 complete with fast charger and intended for use with their chainsaws and lawnmowers, so should be capable of delivering enough current. He used it on his Brompton and got a range of 13-16 miles.

It weighs only 1.24kg, so would be much lighter. I can't see a the dimensions mentioned anywhere so you'd have to go into a store to measure it, although even if it did fit your existing box you'd want to mount it separately so you could remove it easily for charging.

One problem using them with the Heinzmann is that the controller will lack any low voltage cut-off which is required to protect lithium batteries from over discharge. It's possible this might be built into the battery, I see it has a battery meter, but it might also be built into the appliance it's intended. for use with. This would require further investigation.

If you're interested in reading the short atob article you can download that issue 101 for 99p here.

Hello again, I have to admit I did find the 4Ah a little on the small side, by the time I got the bike the battery was only good for 8 miles, 4 miles into town and 4 miles back, but only just. I thought if I were going to replace it then something with a bit more poke and a wider range would be preferable. I quite like the idea of buying a clutch of NiMhs and soldering them together, but I may be being seduced by the cheapness of this option. I have discovered that if I buy a lithium ion replacement that I would need a replacement controller too which also adds to the overall price. The range of batteries looks pretty big and the price varies too but I have yet to find any for under £199 which seems a bit steep, and I have no idea if these batteries are any good and I'm reluctant to spend so much on something I know very little about or know anyone else who can recommend them. They all seem to come from China too. That is why I thought the forum was a good option. Thanks for all the ideas and advice so far, its all very interesting and I'm very grateful.

 

[hoppy]

Hello again, I have to admit I did find the 4Ah a little on the small side, by the time I got the bike the battery was only good for 8 miles, 4 miles into town and 4 miles back, but only just. I thought if I were going to replace it then something with a bit more poke and a wider range would be preferable. I quite like the idea of buying a clutch of NiMhs and soldering them together, but I may be being seduced by the cheapness of this option. I have discovered that if I buy a lithium ion replacement that I would need a replacement controller too which also adds to the overall price. The range of batteries looks pretty big and the price varies too but I have yet to find any for under £199 which seems a bit steep, and I have no idea if these batteries are any good and I'm reluctant to spend so much on something I know very little about or know anyone else who can recommend them. They all seem to come from China too. That is why I thought the forum was a good option. Thanks for all the ideas and advice so far, its all very interesting and I'm very grateful.

Have you tried Cyclezee? He sells Heinzmann now, as well as other makes, and might help.

 

[Guy Levy]

Hi again,
I haven't tried Cyclezee and it may be helpful for me to contact him, do you have an email for him or does he have a website? I have decided after much consideration and a chat with a mate to go for the NiMh option as it seems the cheapest and means I can still use my original charger, battery box and controller, or I can according to a friend of mine. If anyone has any further info that may be useful to me on this topic or knows something about these batteries that I really ought to know please let me know.
Thank you all for your help and suggestions so far.
Guy

 

[flecc]

Here you are Guy:

cyclezee@gmail.com

You can use your existing charger with NiMh replacement cells so long as you include the existing NTC thermistor connected in the same way, and the cell size being the same means the battery case is also ok.
.

 

[hoppy]

Here you are Guy:

cyclezee@gmail.com

You can use your existing charger with NiMh replacement cells so long as you include the existing NTC thermistor connected in the same way, and the cell size being the same means the battery case is also ok.
.

Website cyclezee.com. John is very experienced and knowledgeable and may be able to give helpful advice. Do let us know if the nimh replacement is successful.