External Battery for winter ride

[donnybike]

I assembled this mount for an external battery connection.
The battery used: CR123 3V Photo Lithium

exbatt1.JPG (129.12 KiB) Viewed 9591 times

exbatt3.JPG (139.02 KiB) Viewed 9590 times

Donny
Tx

[rruff]

That's cool... did you solder the wires directly to the battery? I thought that was a no-no but maybe I'm wrong. I expoded a Lithium battery once doing that...

I'm planning to hook one of those up as well. I think I'm going to make a groove in the front of the stem to pass the wires through, and put the battery inside the stem.

[jim_s]

So the big question is, how did you get inside of the mount?? I've tried several times to get the mount apart, but my better judgment stops me each time, as I'm afraid of destroying the mount in the process of trying to open it up.

[rruff]

You can buy the "kit" from Velocomp... the mount is apart to allow access, and then you glue it together when done.

[samisrour]

Has anyone try to put several LI batteries in parallel to significantly increase the capacity.

[rruff]

They won't fit in the device, so there is no point. You can get larger capacity batteries if you are going to go external.

[Russ]

If I was going for more than a CR123, I think the next step is two of these in series:

http://www.batteriesplus.com/pc-25833-2 ... 1BP-2.aspx

These are AA size 1.5 volt lithiums at 2900mah so in series, 2900mah at 3.0 v!
For some reason they do not list the mah on their cr123. Another site showed
the duracell cr123 at 1550mah so maybe two of those in parellel would be
even better.

But batteries plus will (for a fee) spot weld solder tabs on the batteries and
even solder in leads and heat shrink over the whole works (make sure to specify
that the shrink wrap be installed in a way for the leads and all to best fit inside
your handlebar or whatever you plan to do.

Of course you need to get the external battery mount kit from velocomp

[rruff]

But batteries plus will (for a fee) spot weld solder tabs on the batteries and
even solder in leads and heat shrink over the whole works (make sure to specify
that the shrink wrap be installed in a way for the leads and all to best fit inside
your handlebar or whatever you plan to do.

I just bought the kit, so I'm looking for the other parts. I don't see anything on the Batteries Plus website about welding tabs. Some places sell batteries with tabs on them, but they are quite expensive. This place has a cheap holder and batteries, but shipping is expensive: http://www.batteryspace.com/index.asp?P ... tegory=881

Any other ideas?

[Steve_Davidson]

But batteries plus will (for a fee) spot weld solder tabs on the batteries and
even solder in leads and heat shrink over the whole works (make sure to specify
that the shrink wrap be installed in a way for the leads and all to best fit inside
your handlebar or whatever you plan to do.

I just bought the kit, so I'm looking for the other parts. I don't see anything on the Batteries Plus website about welding tabs. Some places sell batteries with tabs on them, but they are quite expensive. This place has a cheap holder and batteries, but shipping is expensive: http://www.batteryspace.com/index.asp?P ... tegory=881

Any other ideas?

Ron,

I couldn't get a hold of a CR123 battery box so I just got a piece of plastic pipe and made a holder for the CR123 cell without soldering any connections on. I just taped the connectors onto the cell and shoved it into the plastic pipe (with a slit down one side for the wire) and then taped it under the stem.

For a neater solution you could use longer wire and run it under the bar tape so that you can put the battery box inside the bars and hide it with the end plug. Michael Toporowski suggested this tip a long time ago when he came up with the idea for the extra cell (and done a neat job).

cheers


Steve

[Russ]

I went to a Batterys Plus store here in town and they had the spot welder siting there onsite
and the sales/tech offered to spot weld on the solder tabs. Try calling a store, if you are not local to one.

Russ

[rruff]

I couldn't get a hold of a CR123 battery box so I just got a piece of plastic pipe and made a holder for the CR123 cell without soldering any connections on. I just taped the connectors onto the cell and shoved it into the plastic pipe (with a slit down one side for the wire) and then taped it under the stem.

For a neater solution you could use longer wire and run it under the bar tape so that you can put the battery box inside the bars and hide it with the end plug. Michael Toporowski suggested this tip a long time ago when he came up with the idea for the extra cell (and done a neat job).

I wondered if just taping the wires on would give a reliable connection. I guess you stretch the electrical tape and it should be fine.

I'm planning to stick mine in the stem since it is right there. I'll need to make a groove in the stem at the clamp that is big enough to pass the wires, but it should work ok.

[racerfern]

I have to recommend against both of your ideas. Taping on the connection (it will fall or vibrate off) and you will end up with a scaling on the battery that will prevent proper voltage.

I also think cutting a stem however slight is asking for a material failure. The stem has most of your upper body weight on it and you could weaken it to the point of failure.

Surely you know someone with a soldering iron that can solder the wires onto the battery. Then slide it into the handlebar end and run the wire up the bar; ideally under the tape.

[rruff]

I exploded a Li battery once trying to solder leads to it... not recommended. It was a small 2032 battery, but still I'm leery of trying that again. The site I linked to has cheap holders which should work ok.

As for the stem, the slot will go directly on the side... which is the neutral axis for vertical bending. It isn't a superlight stem or anything.