Rechargeable Battery - Experiences

[vipermania]

Hey All,

I was wondering who has tried using a rechargeable (14500) battery in his/her OSTC-sport (or other dive-computer that works on the AA's)

What brand did you buy?
What's the capacity ?
What's your opinion on this battery ?
Where did you buy it ?

This might be a good topic to gather all details so any interested can pick up the best battery for his/her needs ...

[vipermania]

I have purchased some Nitecore (NL147) 750Mah rechargable 14500 batteries
(Nitecore NL147)

I have not yet tested them since my initial SAFT battery is still ok for now.

But I've done more research and it seems the following battery is also a very good one :

Keeppower 14500 review

Does anyone have any (other) experience ?

[Motardplongeur]

Hello,

Somebody has a "retex" on using rechargable batteries ?

Does it work or not ?

If yes, what is the duration ? (approx, if it needs to open very often the battery compartment, it is not a good idea !)

[SirNoahFell]

Hi,
we bought some Nitecore (NL147) with 750 mAh. But the length is not as defined on the nitecore website (real length: 54mm) such that they don't fit in OSTC3.

The service told us we can use the Nitecore 14500 IMR 650 mAh. But with those you need to be really careful! They don't prevent exhaustive discharge. So if batter voltage becoms lower than 2,7V they might get damaged and also damage yot OSTC.

UPDATE: We now tested the Nitecore 14500 IMR 650 mAh. They fit in the OSTC 3. I try to give an uptate about battery lifetime.

regards,
Florian

[cyberdiamond]

Using a freshly charged 900mAh (tested and confirmed with my analyzer charger) 14500 li-ion battery.

I got 13 dives with 15.5 hours total of diving split over 2 long weekends with a weekend break in between the dive trips.
The ending voltage right after the last dive was at 3.69 volts.

It then also had enough battery power to download the dives by bluetooth afterwards (but I would not do any more dives when it's below 3.7v)

Also just for comparison my backup Shearwater Petrel 2 with the same freshly charged battery lasted the exact same amount of time also ending at 3.6v after the last dive.

Now the thing that would have helped conserve battery power is that I was diving in dark caves so with the screen brightness on auto it should have dimmed down a lot compared to diving in the ocean with the sun shinning.

[heinrichsweikamp]

cyberdiamond Wrote:
-------------------------------------------------------
> I got 13 dives with 15.5 hours total of diving
> split over 2 long weekends with a weekend break in
> between the dive trips.
> The ending voltage right after the last dive was
> at 3.69 volts.

In Eco the OSTC3 consumes around 25mA at 3,7V. So you could easily have done another 15hours of diving with the battery. Ok, cave divers are usually extra conservative but the battery was far from being empty here.

Btw., OSTC #756 should not be a Bluetooth device (USB ).

Regards,
Matthias

[vipermania]

Hi Matthias,

What is the "advised" remaining voltage before we should recharge the batteries ?
I have an OSTC sport #12343 ?
I assume the voltage seen in the "information" menu is a true read-out and not something calculated like % remaining ?

As a result that should be a more reliable indicator of when to charge the battery ?

Thanks,

Tom

[heinrichsweikamp]

Voltage is not a good indicator for Lithium batteries (Primary or rechargeable) since it heavily depends on the load and the temperature.

Regards,
Matthias

[vipermania]

So with a 750mAh Lithium 14500 battery there is no real indication on when to recharge ?
just better safe then sorry and doing it around the 60% remaining mark ?

T.

[heinrichsweikamp]

It's all about the capacity, not voltage. The non-rechargeable Saft LS14500 has 2400mAh, 750mAh are ~1/3 of that so the % display will be ~65-70% when you should recharge the battery.

regards,
Matthias

[vipermania]

Ok that answers it clearly ! Thanks Matthias and keep up the amazing work you guys are doing !