Most of the original batteries in these cameras left are dead.
You may find the ready-made solutions expensive. If you are skilled in simple electrical work and soldering or DIY work, here is the alternative to the custom-made or new old stock original battery blocks.
The original battery block of 4008 series consists of 6 Ni-Cad button cells having 1.2V (total 7.2V), and 250mAh capacity each in a battery pack. In case of 2008 series, 4 Ni-Cad button cells having 1.2V (total 4.8V), and 250mAh capacity each in a battery pack.
You may choose classical Ni-Cad or newer technology NiMH chemistry for the battery pack. Ni-Cads are good for non-frequent use and as a cheaper alternative, where NiMHs are good for frequent use without any memory effect and higher capacities available in smaller sizes compared to Ni-Cads. Since these cameras don’t need higher currents, NiMH is a better choice. Well, higher capacities mean bigger battery sizes (think of the battery block housing of the camera), so its well enough to use 400 to 750mAh batteries, these should work well for regular shooting days. If you need more energy, it’d be better to use an external battery pack, because you gonna need more space laterally added to the battery block housing (may need an extra tube mounted on the camera assuming you have a battery block and disassembled the battery block already, or the diameter of the camera battery block and housing may be not enough for that battery pack, also it may be an ugly alternative cosmetically).
In any case, do not use any Li-Ion batteries! Lead Acid (Pb-Acid) batteries may be used safely.
The battery block housing has three contacts: ground (-), full battery voltage (+) and ½ (half) of full battery voltage (+).
The ½ voltage is needed for iris diaphragm (aperture override) micro motor for a full automatic exposure (S stands for Système sensitométrique in 2008 and 4008) of REGLOMATIC system lenses via the proper lens mount contacts (REGLOMATIC is a Beaulieu patent for automatic diaphragm system).
There is no need for the ½ voltage for non-REGLOMATIC system lenses, but it’s possible to use them semi-automatically (manual) thanks to camera’s internal exposure metering system.
The full battery voltage is needed for camera drive motor, internal exposure measurement system, and electric zoom servo motor (ZM in 4008 series only, they have also iris diaphragm motor, of course.) of REGLOMATIC system lenses via the proper lens mount contacts.
Let’s know the battery housing and cover depth:
What if you don’t have the cover?:
If you would have longer-sized battery configuration, commercially available extension tubes may help (M42X0.75).
The inside surfaces of the genuine Beaulieu covers are dielectric!
Let’s know the battery dimensions (for illustration purposes):
3.2V (3 x 1.2V each, for 4008 2 packs needed), or 2.4V (2 x 1,2V each, for 2008 2 packs needed) cordless phone battery packs with red (+) and black (-) color wiring (ready-made and simple to connect several packs)
Let’s find the correct size, if you want to keep the original spacing:
Single rechargeable batteries such as 6 pcs. of GP-25AAH 1.2V 250mAh NiMH cylinder cells (14.5 x 16.6mm each) will perfectly fit with the cover threaded, or button cell sizes may be tried as well (may be difficult to make a pack, needs special battery welding, or a quick soldering with low temperature usually, 8W USB powered soldering irons available for this purpose), and knowledge to connect the correct polarities, so a battery specialist may be needed – NEVER use excessive heat soldering!).
Use proper size female spade connectors and different color wires (not seen) with heat shrink tubes wrapped for the camera battery contacts (3 pcs. each). So you can switch the multiple battery packs.
Let’s learn how to connect the polarities properly (for illustration purposes):
For 2008 series, use 4 single batteries instead of 6.
Connecting the battery packs with wires is easy, so no need to explain here.
Let’s learn about the battery chargers:
The genuine charger rated at 30mA is for genuine 250mAh Ni-Cad batteries, because generally about the 1/10 charging rate is used for those Ni-Cads. Also, the charger output voltage must be more than 7.2V (4008 series) or 4.8V (2008 series) battery voltage, so a 12V charger is supplied.
Always use a proper charger or mode for correct battery chemistry (Ni-Cad, NiMH, etc.), as well as having the max. current (generally mA is given) that isn’t less than the battery capacity (mAh or Ah). The batteries will get the proper current they needed. Trickle charging is a highly recommended method for longer life of batteries.
Pay attention to the plug polarities of a third-party charger, if it has no short-circuit protection, otherwise the internal resistor may damage despite that resistor is highly resistant to short-circuit.
The power adapters may be used for charging purposes, although it’s not recommended.
Also, before charging do not place the three-position power supply handgrip switch in the red dotted rearmost position!
When a replacement eye cup is also needed, Nikon Eye Cup DK-19 fits perfectly. There are two types: