SPEC POINT CONCEPTS
BATTERIES FOR THE SERIOUS RACER AND RC ENTHUSIAST

RECOMMENED CARE FOR NIMH BATTERIES

Maximum battery performance and maximum battery life rarely go hand in hand. It is SPC’s™ goal to optimize battery performance AND battery life.

If you are a sponsored racer or you are fortunate enough to not have to pay for your batteries you may want to stop here. For everyone who buys their batteries and wants to get the most from their investment, these instructions are for you.

EnerG 4600’s™

Charging EnerG 4600, Sub-C Type, Nimh Packs:

SPC™ does not recommend cycling newly assembled packs with a charger/discharger. During the matching process the individual cells were cycled numerous times. After assembly and before first use, discharge assembled pack on a Novak Smart Tray or MuchMore CTX-D2 tray to 0.9 volts/cell. This is very important! After traying allow the pack to cool completely before charging.

Charge with a NiMH compatible charger that has adjustable voltage cutoff (threshold) capabilities. Check your charger’s operating instructions for specific setup details and set the adjustable voltage cutoff to 10mV to 20mV total for the pack or 3mV per cell. If you have access to a digital temperature gun, take a temperature reading of the pack immediately after charge completion. If necessary, adjust the charger voltage cutoff (threshold) so that the final temperature for the charged pack never exceeds 120° F. Charging-pack temperatures over 120° F will reduce pack performance and operating life. After a pack has peaked remove it from the charger, do not allow it to trickle charge. Trickle charging after a peak charge will generate heat that may damage the pack. Try to time charging so the pack finishes just before your race. If the pack sets for 5 to 10 minutes before race time, re-peak it for a minute or two at 5-Amps. If it sets for more than 15 minutes (it's cool), re-peak at 5-Amps. When re-peaking, monitor the pack to prevent it from over heating. NEVER leave a charging pack unattended. Lastly, don't attempt to charge a pack that is unreasonably cold. If the pack temperature is below 40 F, allow the pack to warm to room temperature before charging.

Race Use - EnerG 4600, Sub-C Type, Nimh Packs:

If done correctly an EnerG 4600 battery pack can be raced/used many times in one day without pack damage. For example, charge then race a pack in the first qualifying heat. After the qualifying heat, remove the pack from your vehicle and allow it cool. It is not necessary to completely discharge the pack after the first run of the day. For cooling, place the pack on the floor or in front of a cooling fan. It must set for at least one hour, hopefully two hours and be completely cool before recharging. After the cooling period, recharge the pack in time for the main.

Maintenance Discharging - EnerG 4600, Sub-C Type, Nimh Packs:

If a pack is unusually hot after use, wait for it to cool before discharging further. A discharge rate of 10-Amps is a good, moderate discharge rate, but any reasonable rate up to 30-Amps is acceptable with the following exception: Except for testing purposes, avoid discharge rates greater than 30-Amps. High discharge rates create extreme heat and extreme heat kills batteries!

As a pack, never discharge any EnerG 4600 Nimh below 1.1 volts per cell; or 4.4 volts total for a 4-cell pack, 6.6 volts total for a 6-cell pack, etc. NEVER run a pack down until your RC car is just barely moving. Never discharge EnerG 4600, Nimh packs with light bulb strings that do not have automatic low voltage cutoff hardware attached. NEVER dead short your Nimh batteries or cells! Dead shorting causes permanent cell failure! Plus the potential for personal injury is very real. EnerG 4600, Sub-C Type, Nimh cells are very sensitive to over discharging. It is better to never discharge them after a race than to over discharge them. DO NOT OVER DISCHARGE YOUR EnerG 4600, NIMH PACKS!

Storage - EnerG 4600, Sub-C Type, Nimh Packs:

How a pack should be stored depends upon how long the pack will set before being used again. If you know you'll be racing again within a week, discharge your pack to 1.1v/cell, re-charge it for 15 minutes or so, then store in a cool, dry area. If a pack will set for more than a week, fully charge and store in a cool, dry area. Re-peak pack every 2 weeks of storage.

ASSEMBLY PRODECURE FOR SUB-C NIMH BATTERIES

Sub-C Battery Assembly:

Wipe the cell ends clean with rubbing alcohol or electrical motor cleaner. After aligning the cells in a soldering jig, apply a small amount of a quality soldering flux to the cell ends and battery bar ends. Do not tin the cell ends or battery bars. Lead is great for soldering but is a relatively poor electrical conductor.

A good solder joint will have smooth, consistent solder flow around the bar end, with minimal solder between the bar and cell. Place a battery bar across two cells; melt a modest BB-sized amount of solder to the tip of a high quality, hot, soldering iron. While holding the battery bar tightly to the cell, apply the iron tip to the battery bar. The solder should immediately flow over and around the bar and to the cell. Remove the iron while continuing to hold the bar down and allowing the solder to cool. If the solder does not flow smoothly within 1 to 3 seconds, remove the iron. Wait for the cell to cool completely before attempting to re-solder. Do not hold the soldering iron to a cell for more than 3 seconds. Serious cell damage will result!

The EnerG 4600, Nimh cells are especially sensitive to soldering-heat related damage on the positive terminal! After obtaining a good solder joint, repeat for remaining cells. .