Replacement battery options ?

[Wizard9956]

Hi all , my present SLA batteries ( 3 off ) measure 100mm High x 110mm Wide x 85mm Depth , as far as i know these size batteries are no longer made , so could anyone recommend any batteries that would replace these and fit in the case to the dimensions above or smaller , i have worked out they are 7 amp hour not 10 amp hour as i thought .
I've found these on the internet Batterymasters.co.uk - Product Details - NP7-12, 7 Ah 12V
But it would mean cutting the side of the case out to get them to fit , which is not really what i'd want to do if possible . I don't have pots of money so Li-ion batteries are out of my price range .

Thanks Wizard

Ps just realised i've asked this question before , but any other battery choices would be greatly recieved .

 

[flecc]

I'm afraid you may have to cut the case Wizard, since after a year of searching the original size hasn't been found by someone else in this forum , so it seems to be defunct.

At least these would get you going again.

As said before, other types are much more expensive and would also need a new suitable charger at still more expense, so these are about your only option to get it running properly.

One other option though. Please don't take this the wrong way as it's intended in the right spirit. You could just resell the bike and start again, taking care to buy a bike with batteries that are still available. As you've seen, you can get help in the forum first with any prospective purchase to avoid mistakes, since there are plenty of dud bikes out there.
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[Wizard9956]

Thanks for the advice Flecc , i haven't taken it the wrong way no worries , i will persevere with this bike , i've tweaked it and rode it over the last 3 weeks , and now even though there's a few hurdles to over come with batteries , it's something i can't give up on just yet . The battery i've found so far that will fit in the case is a 12v 4.5 amp hour , what i'm not sure of is how much range that will give me . But at £4.99 for each battery it's got to be worth a shot .

atb
Wizard

 

[flecc]

That's my pragmatic way with these things, just try it out if it's cheap.

I think there's a fair chance they'd be just enough.
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[Capn_Phil68]

Hi Wizard,

My battery pack is exactly the same.

At the moment my batteries are ok (fingers crossed), but when the times comes for a change I will use the original battery container as a tool/ wet weather lockable storage compartment and mount new batteries under the, yet to be fitted, pannier rack. Probably larger cells in an under rack enclosed shelf. Might be a workable solution?

 

[Wizard9956]

So far i've found this Battery for Bicycle and Motorcycle (6-DZM-7), China Battery for Bicycle and Motorcycle (6-DZM-7) products- China Battery for Bicycle and Motorcycle (6-DZM-7) Manufacturer, supplier the part number on my battery is 6-DZM-7 , but when you look here Wuxi Pufa Power Co.,Ltd. the case size is different , the next one down 6-DZM-8 has the right case size .
Have found this too </title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> <title> - Electric Vehicle Batteries it is 6mm bigger than my battery ( 110mm mine , thiers 116mm ) http://www.greensaver.cn/en/Product/manage/upload/picupload/sp7-12-.jpg
Also found here Electric Bicycle Battery , but correct size makes it a 6-DZM-8 .
atb
Wizard

 

[flecc]

The 6 DZM-8 on the WUFA site does have a worrying point though, which might account for the part number difference and the slightly higher capacity of 8 Ah on these. It has in brackets afterwards (5 hr), which could mean that's it discharge rating. That would be nowhere near enough for an e-bike motor which would need at least a one hour capability.

These SLA batteies have been made in two types in the past, both high discharge like those we need, and a different form made for burglar alarm backup and the like, where very long life is more important than a high discharge rating.

The 6 DZM-8 might be one of that type, so there may be a risk of inadequate performance in buying those. An email to them might clear that up.
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[Capn_Phil68]

# two types in the past, both high discharge like those we need, and a different form made for burglar alarm backup and the like....#

Hi Flecc,

More than a little confused now. Does a 5hr discharge rate mean the battery will power applications at low amps e.g. for 5hrs rather than allow for heavy amp draw "bursts" for shorter periods?

 

[Wizard9956]

Hi Flecc , could you give me a quick run down on discharge ratings and how they apply to ebikes , on the battery websites i've been on , they say MAX discharged current 75A (5secs) , what should i be looking for higher or lower ?

Thanks Wizard

 

[flecc]

Not to worry Wizard, if they say up to 75 amps in seconds, they're perfectly ok. I was just a bit suspicious in case the 5 hours represented the minimum time over which the current could be drawn, which would indicate a low maximum discharge rate.

The figures are presented in different ways so aren't wholly reliable, but you should look for high discharge rates for use with motors, since they can demand very high currents up to 20 amps during high load situations like hill climbing.
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[PaulC]

The obsolete 24Volt Merida electric bike that I bought cheaply (their demo model) from one of the two e-bike dealers in NZ did not come with the original set of 2x12Volt 9AH SLA batteries.
The original batteries had died of old age so the dealer replaced them with 2x12Volt 12AH SLA batteries which were too large to fit in the bike's battery container.
Instead he fitted one battery in the container and the other battery was tied to the top end of the rear carrier /luggage rack. The battery on the carrier rack has 2 thick copper wires from its terminals going back into the battery container (through a small hole) where I assume they are joined up to the wiring. That way the container has no large holes or cuts in it. The power range is increased as well.
This works OK for me as I use panniers that clip on the side of the carrier rack, so I have never used the carrier top for anything.
Sorry but I don't have pictures to show you what this looks like,
Paul

 

[Mandy]

Battery Replacement for Powabyke

Hi Guys
I am probably in the totally wrong thread here but if you have a powabyke and need to replace the 3 batteries enclosed in the casing then this can easily be achieved yourself but you guys probably know that already lol!
If you arrange for this to be carried out by a reputable dealer it can cost upwards of £85.00. If you purchase the 3 batteries on the net with no postage cost this will cost just over £60.00.
I did not keep the link but am sure you would be able to find it with a search or I can assist you.
You would require a good soldering iron and some basic knowledge of electrics but could save you some money and why wait a week?
Take photo's when the casing is off and this will assist you as to where the cables need to be attached.

Whilst electric bikes are not my forte guys, I would like to say that I had been a supervisor in a production enviroment which produced contact lenses on CNC (Computer Numerically Controlled) lathes (You knew that too didnt't you, lol) for 19 years until my redundancy in 2004 due to the company relocating.
I was the only female within that production enviroroment that would assist our maintenance department in the maintaining of the machinery.
I was respected and trusted by these guys and would be approached to remedy problems. I used mag base clocks, micrometers and of course allen keys to assist me in diamond tooling to ensure they were placed in the correct place on the machine to avoid a point on the tiny finished contact lense. Never used a hack saw Johnny? lol!!
I worked to .002 of a micron as the CNC lathes needed much manual adjustment and bearing in mind we made contact lenses this would be the measurement required and this blonde lady has not misplaced her decimal point as this was .002 of a micron by eye, clock, magnifier and determanation!! lol! My maintenance department made me a special little step to actually reach into the machine's as I would use a stool otherwise and I need one to get on the bike but do not work there anymore, I am now an office worker and miss my machinery and the oil on my hands but can't due to my back problem.

I have also fitted a suspended ceiling to my stair well, hung door's using a plane, not a hack saw, lol Johnny, fitted taps, fitted shelves, tiled, fitted skirting, boxed in pipes beautifully, plastered etc etc etc!!! lol!
So if you want info on revamping your LEAD ACID battery? email me.
OK, however I do not know anything about the current one's, lol!!!

Regards

Mandy

 

[Wizard9956]

Hi Mandy , your experiance sounds great , i've been a machinest for 25years working about 25-30 different cnc's , manuals , splining machines etc . Also big diy fan , fixing just about everything you can think of . Now i'm a fully trained fitter ( aircraft ) .

atb

Wizard