California Department of Transportation
 

4. BATTERIES

4.1 General

Disconnect batteries and all power sources before doing any electrical work. Before welding or cutting, disconnect all sensitive electronic assembly or devices.

4.1.1 Battery Types & Terminology

  1. Battery terminology is not standardized but distinct battery types are intended for different uses. Batteries used for starting cars and trucks are commonly referred to as "flooded", "liquid" or "wet" batteries.
  2. Deep cycle lead acid batteries are usually designed with thicker plates and are intended for slower and longer discharge cycles. Typical applications include auxiliary equipment power supply or solar powered applications. Deep cycle batteries are of the liquid type, "gel" type or "AGM" type (Absorbed Glass Mat). Both gel and AGM batteries are sometimes referred to as "sealed" batteries. Both gel and AGM batteries require special charging voltage, current set points and control logic.

4.1.2 Battery Installation

  1. Battery installation shall comply with the requirements set forth in the Federal Motor Carrier Safety Regulations §393.30 Battery installation.

    Every storage battery on every vehicle, unless located in the engine compartment, shall be covered by a fixed part of the motor vehicle or protected by a removable cover or enclosure. Removable covers, or enclosures shall be substantial and shall be securely latched or fastened. The storage battery compartment and adjacent metal parts which might corrode by reason of battery leakage shall be painted or coated with an acid resisting paint or coating and shall have openings to provide ample battery ventilation and drainage. Whenever the cable to the starting motor passes through a metal compartment, the cable shall be protected against grounding by an acid and waterproof insulating bushing. Wherever a battery and a fuel tank are both placed under the driver's seat, they shall be partitioned from each other, and each compartment shall be provided with an independent cover, ventilation, and drainage."

  2. Batteries shall not be installed above or below a fuel tank, fuel filter, or fuel fitting. Metal fuel lines within 12 inches of a positive battery terminal shall be insulated with high dielectric material to prevent accidental short circuits.
  3. The positive connection on each battery shall be protected so that metallic objects cannot come into contact with it. This can be done with plastic boots, or shields, or putting the batteries in a covered plastic battery box. Any bus distribution system, inverters, starters, etc., directly connected to the positive side of the battery shall be similarly protected by plastic boots or shields.
  4. Batteries wired in parallel shall be the same type and capacity.
  5. Battery and DC circuits shall be physically separated by at least a ½ inch gap from circuits of a different power source. Wires run inside conduit provide adequate separation.

4.1.3 Battery Compartments

Battery compartments shall be provided in accordance with the following:

  1. Installed batteries shall be held in place by battery hold down clamps and not move more than one quarter inch (0.25") in any direction. Battery hold downs shall not impede normal expansion and contraction of the battery case.
  2. Provide access for battery installation, maintenance, testing, and removal without disassembly of equipment.
  3. Prevent build-up from heat, gasses, liquids, or chemicals released during battery operation, charging, deterioration, or rupture, (e.g., vents).
  4. Prevent build-up of heat, gases, liquids, or chemicals from entering the electronic compartment. (i.e., seal off from other compartments or components).
  5. Installer shall also comply with the National Electric Code (NEC) 551-10d (Battery Installations).

4.2 Liquid Batteries

  1. If the surface the battery is mounted on can be attacked by electrolyte a means shall be provided so that material is not damaged.
  2. Leakage or spillage of electrolyte shall be contained.
  3. Fasteners for battery boxes or tray shall be isolated from areas used to collect spilled electrolyte.
  4. Liquid batteries shall not be installed inside a passenger compartment.

4.3 Deep Cycle Batteries

Deep cycle charging applications (e.g. solar charging systems and inverter power) shall use absorbed glass mat (AGM) batteries. (e.g., Chairman Series, Lifeline Series, Sun Xtender Series by Concord).

Last updated 01/14/04