• The manufacturers should help users insert fresh batteries
correctly into equipment. Recommended battery contacts are designed so that
any battery installed backwards cannot supply power. Insertion of a cell
backwards in a multicell battery can cause cell rupture and leakage. If this
is not feasible, clear instructions are needed. An information sticker or
easily readable instructions molded in the battery compartment are suggested.
These instructions would include type and size of battery to be used, polarity
symbols, and any other special considerations.
• Design water-tight aquatic devices to deal with battery
generated hydrogen, which must be either absorbed or allowed to escape.
Otherwise, certain conditions could trigger the ignition of the entrapped
hydrogen/air mixture and possibly cause a violent rupture.
• Assure safe overboard venting from the device, system,
compartment, vehicle, etc., and allow batteries to expand or contract. For
this reason, avoid encapsulation or potting whenever possible.
• Locate batteries as far away as possible from any heat
source to prevent service life degradation, or provide insulation between the
battery and heat sources such that battery temperature cannot exceed55°C.
• Design devices which have alternate power supply options to
assure that batteries are isolated from the alternate power supply circuit.
Avoid use of external switches activated by the alternate power supply cord;
commercially available generic replacement cords may not activate the
protection switch. Consider redundant diode protection against unintended
• Where metal-jacketed batteries are used, provide additional
protection by insulating the metal jacket from any material that can conduct
electricity. This will help prevent short circuits.
• Design the battery compartment to have a high resistance to
electrolyte leakage. In case of cell leakage, the product can still serve the
user if the battery compartment is designed to minimize any damage.
• Make battery compartments tamper-proof, yet accessible, to
protect untrained personnel who might have access to the equipment.
• American National Standards Institute C.18 and International
Electrochemical Commission 86-1, 86-2 provide guidance for battery compartment
size and contact location.
• Where possible, allow additional space in the battery
compartment for future increases in power requirements. Upgrades and
modifications of weapons systems generally increase power requirements and
often require larger batteries.
• Design the equipment to switch off after the battery voltage
has dropped below the functional limit of the device. This is especially true
of equipment which leaves the battery circuit still completed when it fails,
leading sometimes to cell reversal. This situation will very frequently cause
electrolyte leakage or cell rupture.
• Replace batteries as soon as their performance becomes
unsatisfactory. When installing new batteries, inspect the contact surfaces
and remove any dirt or corrosion.
• Since corrosion can be a problem around battery connections,
it is recommended that all leads used to connect the battery to the system be
provided with sufficient additional length for at least two replacements of
• If the device is not to be used for several months, remove or
disconnect the batteries.