Question on replacing cordless phone batteries

Dec 06, 2003 4 Replies

Hi all:



I have a Lucent/ AT&T cordless house phone(model7720). The rechargeable battery pack needs to be replaced. IT is battery model #4051. 3.6volts,



270mAh.

In a web search I've found several that were listed as being compatible at 3.6Volts 300mAh, and up to 3.6 Volt, 400mAh. Would the batteries with a higher mAh rating be OK, and would they hold a charge longer. Or should I stick with a EXACT replacement. Like to hear from those who know. Thanks.


Hi, RS sells them. Higher capacity ones will last longer per charge. Are they physically same? Tony

yes keep volts the same, but higher amp hr means longer talk time, I always replace with highest amp hr. its worth it.

if you go for the higher mAh rating batteries, no problem if the other way around then it either will not work or not last as long on a charge.. go to

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and they should have anything you want in the line of batteries.. they are pretty cheap compared to local places for most hard to find batteries.. example rech. lattern battery for a lattern, local $35, their price $12.00 burglar alarm back up battery, local $25 and they would have to order it, their price was i believe $16.00??? and a few others that i cant remember, no harm in cheking them out....

higher miliampere hour rating is fine. Just gives y ou m ore talk time between charges.

Voltage needs to be the same.

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