Page 42: of Marine Technology Magazine (November 2022)

LANDER LAB #5 BATTERIES

Illustration courtesy of Witold Maranda, PhD,

Lodz University of Technology, Poland

Progressive RC

Figure 7 Figure 8

An unbalanced smart LiPo charger provides Constant The ESR (Equivalent Series Resistance) Meter Mark II.

Current (CC) initially, then shifts to Constant Voltage (CV) to complete the charge.

protection, over-voltage protection, and reverse polarity pro- 3. The Computerized Battery Analyzer V Pro (CBA V Pro) tection. The smart unbalanced LiPo charger provides a con- I’d de? nitely get this one, too. It’s used to test battery capac- stant current/constant voltage charging cycle. ity and to accurately and automatically discharge a battery to a speci? c voltage for storage or shipping.

IMPORTANT INSTRUMENTS TO HAVE 1. DVM, of course, then it gets interesting. The Storge and Shipping voltages are obtained by ? rst charg- ing the battery, then discharging to the speci? ed voltage using 2. The LiPo ESR (Equivalent Series Resistance) Meter Mark II. the CBA V Pro Battery Analyzer. Specify the end voltage and

Easily the next most important LiPo diagnostic tool to have the CBA will automatically stop when it reaches that voltage.

in the tool chest.

The CBA (Computer Battery Analyzer) V can also determine

Internal resistance (IR) is the best predictor of battery the actual capacity of the battery at different discharge rates. condition. IR is measured in milliohms (mO). The lower the It can also test the Low Voltage Cut Out function (LVCO) of resistance, the less restriction there is current ? ow. High resis- the BMS.

tance causes the battery to heat up and the terminal voltage to drop under load. To test a battery’s capacity at cold temperature, place it in a

The LiPo ESR (Equivalent Series Resistance) Meter Mark refrigerator and run the leads out to the CBA V. An indoor/out-

II is the best meter on the market for judging the quality of door thermometer will provide temperature. ($229, from West lithium battery packs. Mountain Radio )

The ESR meter provides the internal resistance of individual 4. A 5-in-1 Cell Meter to test cell voltage: cells when removed from the battery stack, or an integrated This meter measures voltage of individual cells and total bat- measurement of the entire pack, including the BMS. The tery voltage through the balance plug.

BMS adds a ? xed offset to the battery IR. The ESR provides The Tenergy 5-in-1 Cell Meter can display the estimated re- a direct readout of the Internal Resistance and Max Current maining capacity based on unloaded terminal voltage for LiPo the pack can deliver at the moment the measurement is made. battery packs. Use this meter to quickly check if your battery requires charging before use. It can also display the voltage of

The manufacturer advises measurements be made at the each individual cell, con? rming balance condition.

same temperature. For LiPo and Li-ion battery packs, this cell meter will dis- ($150, Progressive RC play the internal resistance of each individual cell, providing a quick evaluation of the health of the battery. I would use this 42 November/December 2022

MTR #8 (34-49).indd 42 11/28/2022 4:02:10 PM