How do poeple waterproof their batteries?

[herulach]

Just finished a lamp with a cutter 4 Cree MR11 kit & b-flex. Its currently run off a nimh pack in a bottle.

I'm fancying a lipo pack to strap under the stem, basically because bottles look like crap, and I dont like wires.

I'd just go for heatshrink, but I'm not convinced I'd be able to keep the 'balance' lead both accessible for charging, and out of the crap.

Does anyone have any ideas other than using a project box or something?

Cheers Guys

As a bit of an addendum, can yo ubuild up say 4 18650s into a pack? if so can you charge them in series?

 

[dom]

:welcome: Herulac

You can buy premade 14.8V Li-ion battery packs and chargers from BatterySpace, Batteryjunction or All-battery.These haven't got balancing leads -only protection circuit.

For waterproofing you can use Plastidip.

Cheers
Dom

 

[Jarl]

4 18650's charging in series is IMO a big no-no. If one battery is slightly under-charged or has slightly less capacity, then a theoretical discharge would take it down to having 300mah left, while the others have 305mah. Next discharge there's a difference of 10mah, then 15mah. Eventually (you may or may not reach this stage) either the charger overcharges the pack (it needs a voltage of 14.8V to terminate the charge, the lower capacity cell reaches 4V when the others are at 4.2V, so overcharges the other batteries) or the other batteries still have charge when the dodgy battery is empty, and reverse-polarity it. Either way, I don't want to be close when this happens.

 

[herulach]

Unfortunately batterysapces International shipping (in the UK) is ludicrously overpriced ($60), and all-battery don't ship to the UK. Is it reasonably safe to assume that:

[FONT=arial, helvetica]Built-in IC chip will prevent battery pack from over charge and over discharge and prolongs battery life[/FONT]

Is a balance module as well as a protection circuit? In that case, I'm golden, will just sort some plastidip, heatshrink & stick an adaptor on it.

Thanks for the input, presumably theres beamshots availble of these 4 Cree boards so they're not much use? I use a DX P7 flashlight (MTE one) as a headlamp if anyone wants comparison shots.

 

[wildwood]

Hi Herulach,
I build Li-Ion batteries and chargers, (well known on singletrack). Please mail me with what you are lookin for and I'll see if I can sort you out.

All Li-Ion Packs I build contain protection circuit boards along with additional re-settable and non-resettable devices.

Oh, I'm in the UK

 

[dom]

Hi Heulach
What optic did you get with the Cutter kit?
I'm using the triple narrow beam one for the road which is an excellent beam.
The 4 LED could only be better

Good stuff Wildwood -where you been hiding? Lots of people needing battery packs.

Cheers
Dom

 

[Uncle Bob]

:welcome: Herulac

For waterproofing you can use Plastidip.

Cheers
Dom

Waterproofing batteries? That's a new one for me.

Waterproof cases and flashlights, yes. Waterproof batteries? Lithium primaries, for example, need to vent.

Please explain.

 

[wildwood]

Herulac, ygm

Hi Dom,
been looking on this and mtbr for a while now :thumbsup: must admit i pop on for a few minutes and then see the time! you can get so sucked into the posts and how a led project develops through the posts.

You may know me as smudge on the forums in the UK, but someone already has that on here.

As for batteries, I build Li-Ion Batteries in various formats along with their matching chargers. - not a spam, just an introduction on what I can do.

sorry for hijacking post Herulac. As for waterproofing I just pop my pack into a re-sealable sandwich bag and put it into a saddle bag.

 

[herulach]

I got the spotty one, first ride out on it tonight suggests it might be a little bit too spotty, but theres absolutely buckets of light (outshines lumicycle HID at level 3, about 750ma by my rough reckoning.)

As for waterproofing, its for Lion rechargeables (will be 18650s in a kit) and the weather we get round here, having it sat around on the stem means it gets wet.

Hi Heulach
What optic did you get with the Cutter kit?
I'm using the triple narrow beam one for the road which is an excellent beam.
The 4 LED could only be better

Good stuff Wildwood -where you been hiding? Lots of people needing battery packs.

Cheers
Dom

 

[dom]

Hi Uncle Bob
Yes -plastidip on the rechargeables is fine -these have been used for years with no issues i have heard.
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2439

I use the same method on some 14.8V 18650 packs and have had one on my bike for the last year -very necessary as i ride everyday in all weather.

Hi Wildwood -have you thought of putting a post up at BST? Though i suppose shipping them would be a problem?

Hi Herulac
Yes -they are a bit too spotty for offroad on the bars -is that the riding you are doing?

Would be good headmounted though i think.

Perhaps get the wide -as it is around 14deg i think


Cheers
Dom

 

[herulach]

I am offroad mostly. As I say, I've not done a decent night ride yet, still a damn sight better than the 10W halogen I had before. I've a 4 Cree RC-T5 on order, with the intention to drive it from a spare maxflex I ordered and a small lipo pack to sit on my head.

Might go the other way round if the beam patterns suit better

 

[Harpoon76]

Unfortunately batterysapces International shipping (in the UK) is ludicrously overpriced ($60), and all-battery don't ship to the UK. Is it reasonably safe to assume that:
Is a balance module as well as a protection circuit? In that case, I'm golden, will just sort some plastidip, heatshrink & stick an adaptor on it.

AllBattery do ship to the UK and have cheaper prices via their eBay site.

I bought one of these, a 18650 14.8v 4400mAh pack, a smart charger and an extra lead from them. I did have to pay £8 VAT and £8 Royal Mail handling fee but even with that, I think the total cost was about £70. The battery on it's own + shipping should be around £35 to £40 which might squeek through customs.

 

[Cemoi]

Has anyone heard of waterproof (well, at least rainproof, I don't plan to go scuba diving with these) AA battery holder?
The holders sold by batteryspace don't seem to be waterproof at all.
And using Plastidip or the like won't make it, since I want to be able to take the batteries out of the case to charge them individually (i.e. not in series). So I need a case with a seal, like most bike tail lights have.

 

[wildwood]

The only downside is if something goes wrong with battery or charger and then you have shipping costs back to the States,

 

[znomit]

Neoprene baggie with the top folded over and velcro to frame/stem whatever. Have used a nighthawk one and made a few(beer can/stubbie coolers work nicely). Very hard for rain to get in. :thumbsup:

I have a 4 aa nighthawk holder that just goes in my rear jersey pocket. Through all sorts of weather and sweat and keeps running even when the AAs are wet. So dunno how important keeping them totally dry is. :shrug:

Regarding the cutter optics... I have a triple narrow on the roadie and a quad medium on the MTB. Both run at 500mA off dynamo with R2s so 480/ 640lm. Both bar mounted. The narrow is much brighter on the road but kinda sucks on tight corners. The MTB has a nice spread but doesn't have huge throw. They are both well suited for their purposes and really nice beams. :twothumbs

 

[herulach]

Due to the price and effort I've decided to stick with my nimh pack, which is basically two 7.2v racepacks in an old bottle. Equivalent capacity (c 8Ah) would cost a fortune in a lithium. Good idea about the neoprene though, may rip it off for my helmet lamp.

 

[znomit]

Due to the price and effort I've decided to stick with my nimh pack, which is basically two 7.2v racepacks in an old bottle.

Your quad cree won't run at full power off 14.4v. The driver needs 1.1v leaving only 3.3v per led. Guestimating 500mA max. You might notice as you ramp up the 5 light levels the top 2/3 are the same brightness, the driver cant supply the voltage needed. When freshly charged (1.4v per cell) its probably ok but you'll lose the top brighness levels before your batteries are half drained.

 

[herulach]

theyre run in parallel with a maxflex bost driver, another reason I don't want to change packs, would be limited to 3 li-on cells

Your quad cree won't run at full power off 14.4v. The driver needs 1.1v leaving only 3.3v per led. Guestimating 500mA max. You might notice as you ramp up the 5 light levels the top 2/3 are the same brightness, the driver cant supply the voltage needed. When freshly charged (1.4v per cell) its probably ok but you'll lose the top brighness levels before your batteries are half drained.

 

[A123Powered]

Has anyone heard of waterproof (well, at least rainproof, I don't plan to go scuba diving with these) AA battery holder?
The holders sold by batteryspace don't seem to be waterproof at all.
And using Plastidip or the like won't make it, since I want to be able to take the batteries out of the case to charge them individually (i.e. not in series). So I need a case with a seal, like most bike tail lights have.

You could get a pelican or similar case and just add a wire gland or waterproof connector on it with a tail inside to connect to the battery. Weight is a bit more, but if it is done right it would be very watertight.

 

[Cemoi]

You could get a pelican or similar case

Good suggestion, but even the smallest Pelican cases are large enough to accomodate far more AA batteries than I want to use.
I'm looking for a case for 2 or 4 AA batteries, as compact as possible.