by Charlotte Adams
Aircraft batteries are too often taken for granted. That is, until a plane loses electrical power far from home and has to switch to its emergency back-up system. Fortunately the prevailing nickel cadmium and lead acid battery technologies are well understood, while evolving lithium chemistries are becoming more acceptable as proper safeguards are applied.
Battery technology continues to improve and batteries last longer. Maintenance and test equipment likewise continues to develop as microprocessors and software make the gear more capable, flexible, and upgradeable.
It’s hard to overemphasize the importance of batteries. As 14 CFR 23.1353 states, in the event of a complete loss of the primary electrical power generating system, the battery must be able to provide electrical power to loads that are essential to safe flight and landing. For aircraft certified to a maximum altitude of 25,000 feet, that means at least 30 minutes of battery power and for aircraft certified for higher altitudes, that means at least 60 minutes of battery power.
Yet batteries are almost an afterthought for some pilots. Battery-related accidents happen all too often, particularly in general aviation, where some pilots may fly their planes just a few hours a year. The rest of the time the battery may just be sitting there, losing charge and deteriorating without regular care and feeding. One day the pilot comes out, finds that the battery is dead, and then jump starts the aircraft from an external source. Up in the air after experiencing electrical failure, and with no backup battery power, the pilot is lucky to return unscathed. His airplane may be less lucky.
Never, ever jump start or hand-prop start an aircraft that is certified with a starting battery if the aircraft has a dead battery, warns Skip Koss, vice president of marketing with Concorde Battery, a leading manufacturer of sealed lead acid (SLA) batteries. He attributes “at least half a dozen” accidents to flying with dead batteries that were not properly recharged before flight. A dead battery’s state is unknown. It needs to be removed, checked, and charged before takeoff.
Lead Acid Batteries
Lead acid batteries have been around for more than 100 years and are still being used in one form or another by general aviation, military, and some smaller executive aircraft, not to mention conventionally powered automobiles. Unlike car batteries, however, aviation batteries are designed to be lightweight. They can’t take the level of abuse dealt out to automotive equipment. And they need more regular test and maintenance.
Over the years wet cell, vented lead acid batteries have been giving way to sealed, recombinant-gas lead acid batteries. The latter type has the advantage of not requiring to be opened. Sealed lead acid batteries also have a higher energy density than the flooded lead acid devices, according to Concorde. The company supports more than 30 airframe manufacturers, including Piper, Cessna, Diamond, Dassault, and Gulfstream, Koss says. It has more than 100 battery models for use in more than 200 aircraft, according to the company.
Lead Acid Battery Test and Maintenance
Maintaining sealed lead acid batteries is pretty straightforward. You don’t open them, but you do have to check them for airworthiness. “It’s like a tire – you can have a fully charged tire that is worn out,” Koss says. With a new sealed lead acid battery, “you have to check the capacity of the battery at least annually to verify the storage ability for essential power.” Subsequent checks could be as frequent as every three months, depending on factors such as the battery, its percent of capacity, the aircraft, and the usage profile. After a capacity test is completed, the battery should be immediately recharged. A lead acid battery, however, should never be discharged to zero during testing because of the risk of damaging the unit, warns test equipment maker, JFM Engineering. JFM’s test equipment can be used with NiCad or lead acid batteries.
VDC Electronics and COFKO Electronics are among the companies providing test equipment for lead acid batteries. VDC’s BatteryMINDer line of products can be used with either SLA or wet cell batteries. These products can trickle-charge batteries to maintain capacity when the aircraft are not being used.
[fullwidth background_color=”” background_image=”” background_parallax=”none” enable_mobile=”no” parallax_speed=”0.3″ background_repeat=”no-repeat” background_position=”left top” video_url=”” video_aspect_ratio=”16:9″ video_webm=”” video_mp4=”” video_ogv=”” video_preview_image=”” overlay_color=”” overlay_opacity=”0.5″ video_mute=”yes” video_loop=”yes” fade=”no” border_size=”0px” border_color=”” border_style=”” padding_top=”20px” padding_bottom=”20px” padding_left=”0px” padding_right=”0px” hundred_percent=”no” equal_height_columns=”no” hide_on_mobile=”no” menu_anchor=”” class=”” id=””][title size=”1″ content_align=”left” style_type=”double” sep_color=”” margin_top=”” margin_bottom=”” class=”” id=””]CURRENT ISSUE[/title][one_third last=”no” spacing=”yes” center_content=”no” hide_on_mobile=”no” background_color=”” background_image=”” background_repeat=”no-repeat” background_position=”left top” hover_type=”none” link=”” border_position=”all” border_size=”0px” border_color=”” border_style=”” padding=”” margin_top=”” margin_bottom=”” animation_type=”” animation_direction=”” animation_speed=”0.1″ animation_offset=”” class=”” id=””][imageframe lightbox=”no” lightbox_image=”” style_type=”bottomshadow” hover_type=”none” bordercolor=”” bordersize=”0px” borderradius=”0″ stylecolor=”” align=”center” link=”https://www.avm-mag.com/wp-content/mag/flipbooks/AVM-2016-02-DIGITAL/index.php#Aviation_Maintenance_Magazine/page2-page3″ linktarget=”_blank” animation_type=”0″ animation_direction=”down” animation_speed=”0.1″ animation_offset=”” hide_on_mobile=”no” class=”” id=””] [/imageframe][separator style_type=”none” top_margin=”” bottom_margin=”20″ sep_color=”” border_size=”” icon=”” icon_circle=”” icon_circle_color=”” width=”” alignment=”” class=”” id=””][/one_third][one_third last=”no” spacing=”yes” center_content=”no” hide_on_mobile=”no” background_color=”” background_image=”” background_repeat=”no-repeat” background_position=”left top” hover_type=”none” link=”” border_position=”all” border_size=”0px” border_color=”” border_style=”” padding=”” margin_top=”” margin_bottom=”” animation_type=”” animation_direction=”” animation_speed=”0.1″ animation_offset=”” class=”” id=””][title size=”2″ content_align=”left” style_type=”underline” sep_color=”” margin_top=”” margin_bottom=”” class=”” id=””]IssueHighlights:[/title][checklist icon=”” iconcolor=”#81d742″ circle=”no” circlecolor=”” size=”18px” class=”” id=””][li_item icon=””]Getting schooled by Robinson[/li_item][li_item icon=””]The Care and Feeding of Batteries[/li_item][li_item icon=””]Lithium Ion Batteries[/li_item][li_item icon=””]Intelligence: News[/li_item][li_item icon=””]Intelligence: About People[/li_item][li_item icon=””]Intelligence: Aviation Electronics News[/li_item][li_item icon=””]2016 Aviation Maintenance Repair Center Directory[/li_item][li_item icon=””]NEW! Aviation Maintenance Buyer’s Guide[/li_item][/checklist][/one_third][one_third last=”yes” spacing=”yes” center_content=”no” hide_on_mobile=”no” background_color=”” background_image=”” background_repeat=”no-repeat” background_position=”left top” hover_type=”none” link=”” border_position=”all” border_size=”0px” border_color=”” border_style=”” padding=”” margin_top=”” margin_bottom=”” animation_type=”” animation_direction=”” animation_speed=”0.1″ animation_offset=”” class=”” id=””][imageframe lightbox=”no” lightbox_image=”” style_type=”bottomshadow” hover_type=”none” bordercolor=”” bordersize=”0px” borderradius=”0″ stylecolor=”” align=”center” link=”http://www.avm-mag.com/wp-content/uploads/2016/01/AVM_Calendar_2016_FINAL_v10_LORES.pdf” linktarget=”_blank” animation_type=”0″ animation_direction=”down” animation_speed=”0.1″ animation_offset=”” hide_on_mobile=”no” class=”” id=””] [/imageframe][separator style_type=”none” top_margin=”” bottom_margin=”20″ sep_color=”” border_size=”” icon=”” icon_circle=”” icon_circle_color=”” width=”” alignment=”” class=”” id=””][fusion_text]NEW – the large fold out 2016 Wall planner was inserted into the Dec/Jan issue but you can also click/view above.[/fusion_text][/one_third][/fullwidth]