anyone got a vistalight nightstick NiMh

[slaw]

On 2005-03-21, slaw <[email protected]> wrote:
[snippage]
> I had some Li batteries made up for my light set up. 2 7.4V 4400mah
> batteries plus smart charger cost me $156 sent to me from Siomar
> Batteries in WA http://www.siomar.com.

Bwa? I'm not seeing any 7.4V batteries in the "rechargable lithium"
section, nor any 4400 mah batteries.

I'm guessing you're talking about two 2.2AH 3.7V Li+ batteries, which is
fine, except that that translates into either one 4.4AH 3.7V battery
(connected in parallel), or one 2.2AH 7.4V battery (connected in
series). No way could you get 7.4V 4.4AH with less than four of the
2.2AH 3.7V batteries.

Batteries were made to order. They consist of four 3.7V 2.2Ah cells each. Not sure of weight, their damn light compared to the 6V 5AH lantern battery gel-cel they replaced. Measures approx 70mm x 40mm x 40mm. They did muck up my order, in that I wanted the four cells side by side to make flat pack 70 x 80 x 20. They offered to repack them, but I was in a hurry at the time to get them for the Kona 24hr. They still fit fine in a jersey pocket for the helmet unit and I just strap the bar unit under my stem, so the shape is fine for that.

 

[suzyj]

Stuart Lamble wrote:

> At what cost, though? IIRC (and it's been some time since I checked),
> Li+ started at around $100 for the equivalent of a couple of AA
> alkalines (based upon my ancient portable minidisc player, dating back
> to around '98 or '99.) I'm pretty sure prices have dropped since then,
> though -- a quick check says a PowerBook battery is $199.

While that's generally true for notebook PCs and similar, for such things as bike lights, it's fairly easy (and cheap) to get simple packs made up.
Siomar in WA do it, and you can buy individual Li+ cells from places like Batteryspace, along with protection circuits etc to make your own packs. The 18650 cell (18mm round, 65mm long) is pretty much ubiquitous.

> But how much are you paying for said replacement? And *can*
> you get that replacement? Li+ aren't standardised -- you have
> to buy Li+ batteries manufactured specifically for your purpose.
> Good luck if it's a niche product and the manufacturer has moved
> on to different things.

I ratted a notebook battery pack I wasn't using. I could similarly have bought cells off the net, or else bought a generic "7.4V" battery pack, pre-assembled, with protection circuitry already built in. You're equally stuffed if the manufacturer of the NiMH battery you use moves on (and a lot of them are moving on - to Li+).

Regards,

Suzy