Filthy Edna 2
Available to buy online from the Lil' Monkey web shop
In standard form, the Edna 2 battery box uses a single, widely available, unprotected 18650 flat top (or button top) 3.7v li-ion battery.
Unprotected 18650 cells are more size consistent than protected cells, more cost effective, more readily available and more likely to be legitimate !! The best cells are manufactured by LG, Panasonic, Sanyo and Samsung. 18650 cells are currently available up to 3500mAh.
The individual 18650 battery is fitted into box in a battery holder, for reliaible connectivity.
Essential electronic protection for these batteries is incorporated in the battery holder, with additional protection incorporated in the lamp electronics and battery management software.
The battery holder is connected in the battery box with RC connector. Care should be exercised with this connector as it could of course be damaged by careless handling. The advantage of seperate battery holder, over boxes with integrated battery spring clips, is that it is more serviceable, particularly important for caving lights due to the harsh environment they are exposed to. Replacement connectors and Edna battery holders are available in the Monkey web shop if ever required.
The battery holder and battery should be loaded with red / black silicone battery holder leads visible at top of box, and with the RC connector to the side of the battery, as per photos. When inserting the battery holder (with 18650 battery) into the Edna box, take care to ensure that the leads are not damaged. 1S1P li-ion heatshrunk battery packs should be fitted in similar manner.
There are two common approaches to charging an 'Edna' 18650 li-ion battery.
The Edna battery holder can be removed from the battery box and used as a charging cradle for the 18650 battery, in conjunction with our Nora micro USB li-ion charger (available with lamp set or seperately). The Nora charger can equally be used to charge a 3.7v li-ion battery pack, including 1S1P arrangement suitable for Edna.
Alternatively, battery can be removed from the holder and charged in a suitable proprietory 18650 charger, such as the Nitecore i2, which can accomodate 2 off 18650 cells (see Little Monkey Shop).
Edna 2 will also operate from simple 1S1P (3.7v) 18650 li-ion battery packs, with protection circuitry incorporated, and silicone leads. This is a widely available format, or easily constructed. We supply Edna packs, currently using NCR18650 3500mAh cells.
These batteery packs can be charged using the Nora micro USB li-ion charger.
The Edna battery box has been designed to be serviceable with fairly basic skills. Should maintenance ever be required, then the cable gland end of the battery box can also be unscrewed, and if required the cable gland can also be readily removed. We would of course advice against disturbing the cable gland end of the battery box other than for essential maintenance.
As mentioned above, Edna 2 uses an unprotected 18650 flat top 3.7v li-ion battery. Button top 18650 cells are also available in unprotected form, and will also work. Unprotected 18560 cells are around 65mm long.
Protected 18650 cells (also generally button top) are longer than unprotected, due to the addition of a protection circuit PCB on the end of the battery. Consequently, these are not compatible with the Edna battery holder. They are also around double the price !!
And use best quality 18650 batteries capable of delivering full light output on maximum 1000 lumen lamp setting !