Back pack batteries

[davekermito]

Might be a daft question but...

After expending the total usage of the 14aH battery on my Juicy Sport a couple of times now, and my resistance to spending £300+ on a spare battery, has anyone thought of a simple reserve battery that is back pack fitted (with a cable from the bottom to attach to the motor cable).

Just an idea!

 

[Streethawk]

I believe Wisper are working on just such a design DaaBag or something its called?

Also the Montague Paratrooper already works like that.

 

[Deleted member 4366]

What you're suggesting is quite feasible. I've not looked inside the battery box, but somewhere there must be the two wires from the battery to the controller. You'd need to do something like: Break the +ve (normally red) wire and bring it out to a heavy duty three way switch; splice into the original battery negative somewhere and bring one out to your aux battery connector; connect the aux battery connector +ve to the two position switch and then you'll be able to use either battery. The battery will need to be a similar type (same voltage) and enough size to provide the required current. You could mount it on a rack.

 

[stevebills]

I believe most off roaders normally use a back pack with a battery and the idea
has been around a long time

 

[jerrysimon]

You mean like this

You can either build your own, see my thread here or buy two A123 6s1p packs and connect them in series giving you a 36v 2.3Ah pack. As stated you will need to find a way to break into the circuit. Suggest you use a fuse as well.

Mine would provide you with about 5-10miles backup depending on your motor, terain and use. You will also need to buy a couple of chargers as well. Cost of the DIY one is about £60 plus £30-40 for the charger/balancer.

Mine sits in my Brompton front bag with a connector controller also in the bag.

PS or may be worth checking this post which details what looks like a great value 36v, 5Ah battery. Note however, the caveat on more current thirsty applications.

Regards

Jerry

 

[flecc]

Back pack batteries are best for off-roading on the rough stuff, protecting both the battery and the bike from shocks.

Team Hybrid ran an electric bike stunt team using BMX bikes with Crystalyte motors, doing all sorts of jumps and bunny hops, and they used back pack batteries. I remember watching them perform in 2007.
.

 

[Wisper Bikes]

I believe Wisper are working on just such a design DaaBag or something its called?

Also the Montague Paratrooper already works like that.

DaaBag (like a Camelback) complete with 15.5Ah battery and water bladder will be available as a part of the DaaHub Extreem Kit to be launched in September.

All the best

David

 

[davekermito]

Oh well, back to the drawing board!

One day I'll think of something indispensable that no-one has thought of yet!

 

[andrewgardner]

DaaBag (like a Camelback) complete with 15.5Ah battery and water bladder will be available as a part of the DaaHub Extreem Kit to be launched in September.

All the best

David

Sounds good any pictures,

 

[Wisper Bikes]

Only pre production prototype but I will take some images today.

All the best

David

 

[Wisper Bikes]

Here you go

Sounds good any pictures,

Here it is, the production model will have lost the wording such as feel Daa Power!

All the best

David

 

[andrewgardner]

Thanks David it looks good.
How does the cable from the backpack conect to the bike, Ive seen the videos on youtube where the riders fall off but can't see the cable disconecting.

Can you tell me if the motor will be a 100mm width.

Can we buy direct from you as it is a kit or will we have to go through a supplier.


Sorry for all the ?

Andy.

 

[Wisper Bikes]

Hi Andrew, there is a curly cable between the battery and controller.

I will post details on buying ASAP.

All the best

David

 

[maka]

hi david
thanks for all your information. Will it be possible to buy/add the DAABAG option to the upcoming regular DaaHub kit by the end of 2011 (xchange of cables?) or is DAABAG with DaaHub Extreem only (and I have to wait)
thanks
mark

 

[Wisper Bikes]

Hi Maka

You can add the DaaBag to the standard DaaHub kit. You simply place the existing battery inside the battery pouch at the base of DaaBag and use a new curly cable (not shown in picture) to connect the battery to the Dock (the dock is where the battery normally sits). See Anthony's test video http://www.youtube.com/watch?v=-JVmmInVwho the Dock is forward of the seat post tube on the test bike so it's a little tricky to see.

And away you go!



All the best

David