Hope Vision batteries

father_jack

Does anyone make third party replacement batteries for Hope lights? The official ones are too expensive around £75.

iPete

Nope don't think so, had to get a replacement myself, used facewest:

http://www.facewest.co.uk/Hope-Vision-S ... -Cell.html

father_jack

That's the two cell version, mine's the 4 cell.

Just too much, I can get a new set of cree lights for £30.

Ouija

Just buy one of the four cell 8.4v bricks for most of the Cree chinese lights and stick the hope connector on it if different. The wiring should be the same unless the hope has more than two.

father_jack

Doing a search looks like 7.4v

Ouija

Father Jack wrote:

Doing a search looks like 7.4v

7.4v and 8.4v packs are the same. It's down to how some people calculate it. The packs are made up of Li-Ion 18650 battery cells that are 3.7v output wired in 2 series, 2 parallel configuration which doubles the voltage to 7.4v. However, in reality the batteries are 4.2v when fully charged and drop down to 2.9v when drained but battery manufacturers always quote the voltage when the batteries in the middle of it's range (AA batteries are actually 1.9v and drain to 1v, for instance). So the packs that state 8.4v are just quoting the max voltage the pack outputs when fully charged and the ones that state 7.4v are quoting the voltage in the middle of it's drain cycle.

father_jack

What type of connectors are these?

I could buy a ready made pack and replace the connector (or ask for that type to be fitted)

Ouija

Father Jack wrote:

What type of connectors are these?

I could buy a ready made pack and replace the connector (or ask for that type to be fitted)

Looks like a 5.5mm outer by 2.1 or 2.5mm inner DC connector. The Cree battery packs that you can pick up for £12 use 5.5mm by 2.1mm. However, you can buy 2.5 to 2.1 converter plugs if the jack socket on the light has a 2.5mm hole in it's center.

In fact, it might be worth buying the adaptor first and trying it out on your lights. If the lights jack socket fits snuggly into the back of the adaptor without it sliding off too easily then you know it's got a 2.5mm hole and needs the adaptor. If it's not a stiff connection then it's a 2.1mm hole and will work directly with the Cree stuff.

Alternatively, try and stick the pointy end of the adaptor into your battery pack. If it won't go then it's expecting a wider 2.5mm hole (which also tells us the hole in your lights jack socket is 2.5mm and you'll need the adaptor for the cree battery pack to work).

father_jack

Right it's got to the point cabling needs replacing. Perhaps I could use EC 5 connctors?

Replace charger connctor
Replace light cable, terminated with EC5
Replace battery cable, terminated with EC5
Build another pack up, again EC5

Do the packs have PCM protection? Doing a google search for 18650 holders and some have protection circuits on the holder.

Something like this?

http://www.ebay.co.uk/itm/10000mAh-7-4V ... 2a356cc508

Ouija

Says it has over voltage protection so probably has a protection circuit.

Can also pick them up from the UK if your in a hurry.

http://www.ebay.co.uk/itm/UK-TrustFire-8-4V-6400mAh-Rechargeable-Battery-Pack-for-Bicyle-Light-Headlamp-/271335088050?pt=UK_ConsumerElectronics_Batteries_SM&hash=item3f2cd4dfb2

http://www.ebay.co.uk/itm/UK-Shipping-8-4V-4400mAh-Rechargeable-Battery-Pack-for-Headlamp-LED-Bicyle-Light-/271335082401?pt=UK_ConsumerElectronics_Batteries_SM&hash=item3f2cd4c9a1

http://www.ebay.co.uk/itm/4-x18650-Rechargeable-Battery-Pack-for-LED-Headlight-Headlamp-Light-6000Mah-8-4v-/261260261869?pt=UK_SportsLeisure_Camping_LightsLanternsTorches&hash=item3cd45339ed

Or make up your own with a battery holder....

father_jack

concerned that ready made packs don't have protection circuits...need to find out if the hope battery pack has protection, or if it's built into the charger. Believe having two would trip charging circuit early.

Ouija

Never seen a ready made Chinese pack that didn't have a protection circuit (got eleven). Most chargers too as they don't assume the battery is going to have one. Doesn't really matter which one trips first as they are both set to trip at the same voltage. A bigger problem is balancing.

Kieran_Burns

am I being naive / dumb suggesting that you open up the Hope battery pack and replace the cells inside?