Signs Your HDD Battery Needs Replacing: Don’t Get Stuck Mid-Job

If you work in horizontal directional drilling (HDD), your equipment’s performance depends heavily on one simple component: the battery. Whether you’re powering a Digitrak transmitter or another brand of HDD sonde, a reliable battery keeps you on schedule and ensures accurate locates. But like any consumable, batteries don’t last forever—and when they fail unexpectedly, the results can be costly.

The good news? Your battery will often give you warning signs before it quits entirely. Recognizing those signals early can save you from job delays, expensive re-drills, and frustrated crews. In this guide, we’ll break down the key signs your HDD battery needs replacing, along with tips for avoiding downtime and keeping your equipment jobsite-ready.

Drop in Battery Life or Runtime

One of the clearest signs of a failing HDD battery is reduced runtime. If your transmitter used to last a full shift on a fresh battery and now struggles to make it halfway, the internal cells are likely degrading.

This loss of capacity can happen gradually over hundreds of cycles or suddenly after a deep discharge. High-demand projects, extreme weather, and frequent charging can accelerate the wear.

Pro tip: Keep track of how long your batteries last on a typical job. If you notice a drop of 20% or more in runtime, it’s time to start planning for a replacement before failure catches you off guard.

Inconsistent Signal Strength

Batteries that can’t maintain a steady voltage output often cause transmitter signal fluctuations. This can show up as:

• Weak or intermittent locator readings

• Signal dropouts at distances the sonde used to cover easily

• Difficulty maintaining depth or pitch accuracy

If your crew spends more time troubleshooting signal loss than drilling, your battery could be to blame. Even a partially functional battery can produce irregular voltage spikes, causing inconsistent data and wasted time in the field.

Physical Changes in the Battery

Visual inspection is an underrated tool in battery maintenance. Before and after each job, take a moment to look for:

• Swelling or bulging in the casing

• Corrosion around terminals

• Cracked housing or leaking fluid

• Discoloration from overheating

Physical damage can compromise safety and performance. A swollen battery, for example, indicates internal pressure buildup and is a clear sign the unit should be removed from service immediately.

Slow or Failed Charging

If your rechargeable HDD battery is taking longer than usual to reach a full charge—or never reaches it at all—the internal cells may be deteriorating.

Common symptoms include:

• Charger indicating “full” too quickly (false full)

• Battery heating excessively during charging

• Inability to hold a charge after a few hours of storage

A healthy battery should charge efficiently and retain that charge until used. Anything less is a warning sign that replacement is due.

Frequent Equipment Resets or Shutdowns

Transmitters and sondes require consistent voltage to operate properly. A failing battery may cause the unit to:

• Reset unexpectedly during drilling

• Shut down under load even when “charged”

• Lose calibration mid-bore

These interruptions aren’t just frustrating—they can cost hours of production time and risk bore accuracy.

Increased Heat During Operation

Batteries naturally generate some heat during use, but excessive warmth can be a sign of internal resistance building up. As cells degrade, they have to work harder to deliver power, which in turn produces more heat. Over time, this accelerates wear and increases the risk of sudden failure.

Best Practices to Avoid Mid-Job Battery Failure

Being proactive with battery maintenance can extend lifespan and prevent downtime:

• Rotate batteries regularly so wear is spread evenly.

• Store in a cool, dry location when not in use.

• Avoid fully draining rechargeable batteries unless manufacturer guidelines recommend it.

• Use only approved chargers to prevent overcharging or damaging cells.

• Keep backup batteries on hand—especially for high-priority or remote jobs.

When to Replace Without Question

While minor runtime loss may be manageable for a while, these situations call for immediate replacement:

• Visible damage or swelling

• Repeated mid-job shutdowns

• Consistent inability to hold charge overnight

• Safety concerns like leakage or overheating

Cutting it too close with a failing battery isn’t worth the risk—especially when the cost of downtime far outweighs the price of a new battery.

Get the Help You Need from Cortek Power

When you need HDD batteries you can trust, Cortek Power has your back. We supply genuine Digitrak-compatible batteries, chargers, and accessories—in stock and ready to ship—so you’re never stuck mid-job with dead power.

Our team can help you match the right battery to your transmitter, recommend high-capacity options for longer runtimes, and provide bundle pricing for crews who need multiple units.

Don’t wait until your battery fails in the field. Replace it before it costs you a day’s work. Contact Cortek Power today and keep your HDD equipment running at full strength.